bluuebunny/crossref_metadata_2025 huggingface dataset:
Process mineralogy characteristics of a very fine disseminated refractory gold deposit
Authors: Lu Zhongbo , Li Guangsheng , Zhu Xingfu , Cai Mingming , Xu Chao
Published: August 2023

The grade, recovery rate, or leaching rate of gold concentrate obtained by the flotation process or cyanide leaching process of gold ore is low, which is typical refractory gold ore. In order to fully understand the properties of the gold ore and optimize the gold recovery process and indicators, the process mineralogy of the ore was systematically studied by means of chemical multi-element analysis, optical microscope, scanning electron microscope (SEM), X-ray energy spectrometer, automatic mineral parameter analysis system (BPMA), and other test methods. The results show that the average grade of valuable element gold in the ore is 2.98g/t, and the contents of harmful elements mercury and carbon are 0.50% and 0.32% respectively; The main gold ore is natural gold, with a small amount of silver gold and tellurium gold; The main metal minerals are pyrite, pyrrhotite, magnetite, hematite, etc; The main gangue minerals include quartz, feldspar, kaolinite, mica, calcite, etc. Under the condition that the grinding fineness is -0.074mm, accounting for 90%, the distribution rates of single gold and bare gold in the ore are 3.15% and 57.66% respectively, and the distribution rates of gold with pyrite and quartz crystals are 5.77%, and the total distribution rates of the three are 66.58%, that is, the maximum theoretical flotation recovery rate of gold under the grinding fineness, but the particle size and fineness of gold minerals are both 5 μ Below m, the particle size of some gold ores is less than 0.5 μ m. It exists in the form of fine particles, micro gold, or ultra-micro gold, and it is difficult to recover gold by the flotation process, so it is recommended to adopt the whole slime cyanidation leaching process.
Wing Optimization Design Based on Composite Global Hawk Unmanned Aerial Vehicle
Authors: Yang Mingxiao , Wang Sifan , Hu Kai , Liu Tongyan
Published: August 2023

Composite materials have become the approach to solve the high stiffness and light weight of unmanned aerial vehicle structures. The wing had an extremely important influence on the flight of the unmanned aerial vehicle. The optimal composite wing design aroused widespread attention since it enhanced the aerodynamic performance of unmanned aerial vehicles. This article was intended to optimize and design the unmanned aerial vehicle with advantages in aerodynamic performance. According to the parameters of the military-civilian integrated unmanned aerial vehicle, a three-dimensional model of the overall structure of the composite Global Hawk unmanned aerial vehicle was designed. The effect of composite materials on the wing and the optimization of the laminate layup structure were studied. XFLR5 software was utilized to analyze the aerodynamic performance of the wing. The original NACA0012 airfoil and the optimized NACA3412 airfoil of the composite Global Hawk unmanned aerial vehicle were analyzed respectively for structure and performance. XFLR5 software was utilized to conduct flight simulation under the set parameters, and the effect of changing the angle of attack on the wing performance was analyzed. The results demonstrated that the optimized wing outperformed the original wing in terms of the lift, drag, torque, and lift-drag ratio.
The effect of salt tracer dosage on the transport and mixing in a water model of gas stirred ladle with a moderate gas flow rate
Authors: Chen Chao , Allayev Arslan , Li Linbo , Qi Hongyu , Tao Xin , Zhou Feng
Published: August 2023

In water model studies of mixing in ladles, the used salt tracer dosage is somehow neglected. It was reported that the salt tracer might influence the fluid flow and measured mixing time in water models. This study focuses on the effect of salt tracer dosage on the transport and mixing in a water model of a ladle with a moderate gas flow rate. The 1:3 scaled-down water model of an industrial 130 t ladle is established. Both black ink tracers for visualization of the flow field and the salt tracer for measuring the mixing time are used. The results indicate that the main circulation flow is dominant for the transport of the tracer. When increasing the salt solution tracer dosage, the arrival time at upper points is delayed, which indicates that a portion of the salt tracer is flowing downwardly to the bottom of the ladle. Consequently, the salt tracers dispersed to the bottom of the ladle are enhanced and at a faster pace. The mixing time of all monitor points decreases when the dosage of the salt tracer increases. The tendency is even obvious at the top surface.
Super hydrophilic Sodium Alginate Coating on the Surface of Polyvinylidene Fluoride via Freezing and Salting-out for Achieving Emulsion Oil Purification
Authors: Xia Mengsheng , Xu Pengtao , He Qian , Chen Yan , Shi Qian
Published: August 2023

In recent, oily wastewater as a special contaminant has seriously impacted the ecological environment. In this work, nature and green materials are used to prepare the SA-PVDF membrane taking freezing and salt out super hydrophilic modifying. Therefore, obtained membrane exhibited good membrane flux, excellent recyclability, and superior separation efficiency. More importantly, obtained filter membrane was green, eco-friendly, and cost-affordable. Therefore, such a simple, universal, and facile method could be used in other organic and inorganic materials for preparing filter membranes, which plays a significant role in construing novel filtration membranes to remove oil from oily wastewater in practical life.
Low-cycle Fatigue Behavior and Microscopic Morphology of Fatigue Crack Structure of Al-Cu-Ag-Fe-Mg-Zr-Er Alloy in The Aging Treatment
Authors: Zhao Yuhang , Fan Ruicheng , Gao Ying , Li Yifan , Ren Yanjie
Published: August 2023

Al-Cu-Ag-Fe-Mg-Zr-Er alloy with different content of Er addition was prepared by using metallurgy processing. The Al-4.5%Cu-0.5%Ag-0.35%Fe-0.38%Mg-0.1%Zr-xEr alloy phase and its refinement mechanism were studied with SEM. Tensile and fatigue tests were performed for the alloy in the state of deformation treatment condition. The microstructural observations reveal that the addition of 0.2% rare earth Er can effectively refine the grain structure of Al-Cu-Ag-Fe-Mg-Zr-Er alloy. It improves room temperature tensile strength, yield strength, and elongation at break. Under the condition of low cycle fatigue loading, Al-4.5%Cu-0.5%Ag-0.35%Fe-0.38%Mg-0.1%Zr-0.2%Er alloy shows a cyclic strain hardening in the cyclic stress response curves, which mainly depends on forming complex dislocation configurations. The accumulation of slip bands at the front of the grain boundary will lead to intergranular fracture of the material.
Comprehensive Coefficient Correction and Sensitivity Analysis of Important Parameters of Material Fatigue Strength
Authors: Zhang Tiezhu , Zhang Chunfeng , Zhao Haifeng , Ma Liping , Yu Shaoxuan , Yu Wei
Published: August 2023

The study of fatigue strength is of great significance in all fields. In fatigue design, converting the nominal strength of the material into the fatigue strength of specific parts in the working environment is an unavoidable problem in mechanical design. Therefore, it is very important to study the influencing factors of the fatigue strength of parts and how to correct these influencing factors to obtain the fatigue strength of parts. This paper conducts a more systematic study on the fatigue strength of mechanical parts. The effect of the interaction between stress concentration, surface processing, and size effect on fatigue strength is mainly analyzed. A more reliable comprehensive correction coefficient of fatigue strength is proposed, the existing comprehensive coefficient of fatigue strength is compared and analyzed, and the sensitivity of the proposed comprehensive correction coefficient of fatigue strength to stress concentration, surface processing, and size effect is analyzed experimentally. Finally, the proposed comprehensive correction coefficient of fatigue strength is relatively stable and can be applied to mechanical design.
Free Arc Disperses-Sprays Carbon Nanotubes and Silicon Carbide, Preparing Thermal Silicone Grease
Authors: Zhang Chuanqi , Shi Song , Bi Lansen , He Liangqing , Li Wei , He Yan
Published: August 2023

Thermal conductivity grease (TSG) is an important interface material for electronic devices’ heat dissipation. A continuous free-arc dispersion-spraying method of carbon nanotubes (CNTs) and nanocrystalline silicon carbide (SiC) for the preparation of TSG is reported. CNTs and SiC are dispersed and mixed by a free arc and are sprayed on the silicone oil surface (carried by the conveyor belt). Then, the silicon oil is separated from the conveyor belt, and the TSG composite (TSG-E) with highly dispersed CNTs@SiC is prepared. In this work, TSG-E has a CNTs@SiC network with CNTs as the frame and SiC as the node. Compared with untreated (TSG-N), grind (TSG-G), and ultrasonic (TSG-U) dispersion methods, TSG-E has better thermal conductivity (λ) and resistivity. CNTs@SiC network of the TSG-E series affects λ, the effect follows the thermal conductivity network theory and has a sudden change (greatly decreased) from TSG-E0.2 to TSG-E0.3. Besides, the sudden change of thermal stability for the TSG-E series is consistent with the change of λ.
A Fast Reconstruction Algorithm for Stereolithography File Topology Based on Hash Tables
Authors: Wu Yan , Kong Weipeng , Guo Zhiyuan , Han Shizhan , Li Zhaoyang
Published: August 2023

Aiming at the problem of redundant data and loss of original topological relations in the conversion of 3D models into STL files in the engineering manufacturing process, a hash table structure based on the square-taking method and the chain table method is established based on extracting the information storage characteristics of STL files, and a fast reconstruction algorithm based on the hash table for the topological relations of STL files is proposed. The hash table is used to merge redundant point data, and the topological reconstruction of the model is completed by using the point table and face table structure to store the index value relationships of the vertex and face pieces. Finally, four example models are verified respectively. The verification results show that the algorithm reduces the storage space of STL files by 91% on average, and the topology reconstruction time is reduced by 25%, which improves the efficiency of processing such as layering and region division in subsequent manufacturing.
Compilation Optimization of DCU-oriented OpenMP Thread Scheduling
Authors: Zhou Qiang-Wei , Li Jia-Nan , Zhao Rong-Cai , Han Lin , Wang Xin
Published: August 2023

OpenMP is one of the mainstream parallel programming models in recent years. After version 4.0, OpenMP introduced a new target instruction to increase the functionality of heterogeneous programming, called OpenMP Offload. For the domestic heterogeneous platform DCU, the thread scheduling algorithm under OpenMP parallel computing has low performance in the default mode, which does not take the best advantage of GPU parallel computing and has wasted resources. To address this problem, this paper performs algorithm improvement at the compiler level, analyzes the available resources of the system by combining the DCU hardware facilities, then further parses the program based on its array information to get its program iteration number, reallocates the number of threads for different execution modes in OpenMP, and optimizes the thread group increase factor by combining the DCU hardware information to adjust the thread. This paper uses the SPEC ACCEL test set to optimize the number of threads in the DCU. In this paper, we use the SPEC ACCEL test set and Polybench standard test set to test the redistribution of threads and thread groups in two parallel modes using the thread scheduling optimization algorithm. The average speedup ratio of ACCEL was improved by 40%.
Multi-source Distributed Radar-Infrared Track Association Method Based on Spatial Geometry
Authors: Bai Hao , Yang Zhengzheng , Hu Jiangfeng , Mu Yang , Su Xiaolong
Published: August 2023

To improve the accuracy of track association between radar and infrared sensors, a multi-source distributed radar infrared track association method based on spatial geometry is proposed. This method uses rough association and fine association to judge the correlation between radar and infrared tracks. Rough correlation calculates the statistical distance through the weighted norm of the redundant information difference between radar and infrared tracks and determines the rough association threshold by hypothesis testing to obtain multiple radar tracks successfully correlated with infrared tracks. Fine association abstracts the radar and infrared tracks in the rough association into points and lines in space respectively. Through the method of spatial analytic geometry, the distance between the spatial points and lines is calculated, and the association results of radar and infrared tracks are obtained based on the spatial distance. The simulation results show that the performance of the track association method based on spatial geometry is better than that of the nearest neighbor method and weighted track association method in the application of distributed multi-source radar and infrared track association.
Identifying Parameters of Reactor Operation Digital Twin by Using Swarm and Evolutionary Algorithms
Authors: Dai Anqi , Liu Zhenghai , Zhu Tao , Liu Zhengyu , Deng Yan
Published: August 2023

Digital twin (DT) technology is currently gaining popularity in a variety of industrial applications. Recently, the China Institute of Nuclear Power proposed a data driven by nuclear reactor digital twin. The digital twin solves the forward problem for physical field simulation and the inverse problem for parameter identification. The inverse problem can be viewed as a black-box optimization problem where the input parameters are identified by the Latin hypercube sampling (LHS) method based on a given partial observation. While LHS is relatively naive, in this paper, we proposed to apply swarm and evolutionary algorithms to solve the inverse problem. Specifically, we present an experimental comparative study for LHS and four popular SEAs, Particle Swarm Optimizer (PSO), Differential Evolution (DE), Evolutionary Strategy (ES), and evolution strategy with covariance matrix adaptation (CMA-ES). The results show that, for this inverse problem, SEAs are more accurate and efficient than LHS. We also investigate the comparative optimization algorithm’s searching capability under the conditions of noisy observations and no initial input parameter guesses. The experimental results show that DE and CMA-ES have strong robustness and high searching ability.
Feature Fusion Based on Transformer for Cross-modal Retrieval
Authors: Zhang Guihao , Cao Jiangzhong
Published: August 2023

With the popularity of the Internet and the rapid growth of multimodal data, multimodal retrieval has gradually become a hot area of research. As one of the important branches of multimodal retrieval, image-text retrieval aims to design a model to learn and align two modal data, image and text, in order to build a bridge of semantic association between the two heterogeneous data, so as to achieve unified alignment and retrieval. The current mainstream image-text cross-modal retrieval approaches have made good progress by designing a deep learning-based model to find potential associations between different modal data. In this paper, we design a transformer-based feature fusion network to fuse the information of two modalities in the feature extraction process, which can enrich the semantic connection between the modalities. Meanwhile, we conduct experiments on the benchmark dataset Flickr30k and get competitive results, where recall at 10 achieves 96.2% accuracy in image-to-text retrieval.
Design of sensorless permanent magnet synchronous motor controller based on improved sliding mode observer
Authors: Wang Wantong , Wang Yulin , Wang Qiang , Tong Guang
Published: August 2023

Because PMSM needs to install a position sensor in practical application, and the buffeting issue in sensorless control stems from an old SMO (sliding mode observer), an improved SMO is proposed. Stemming from the improvement of the switching function and low-pass filter of the traditional SMO, the chattering problem of the conventional SMO is optimized. Considering the reality that the traditional PI control strategy unable to respond accurately and quickly in the case of current coupling, the current complete decoupling integrates the traditional PI control method is adopted. It can speed up system response and improve system performance. The experimental consequence demonstrates that the improved SMO can effectively restrain the chattering phenomenon and realize the fast and precise control of the PMSM.
End-to-End Control Method for Unmanned Vehicle Based on Knowledge Distillation
Authors: Zhu Bingbing , Gan Haiyun , Lin Weiwen
Published: August 2023

In order to construct a lightweight end-to-end autonomous driving model, knowledge distillation technology is introduced into the construction of the model. The model is composed of a vehicle trajectory orientation marker point prediction algorithm and a motion control algorithm. The prediction algorithm uses the Resnet34 with high precision as a teacher network and the Squeezenet with fast speed as a student network. Based on the knowledge distillation technology, the prediction ability of the teacher network is transferred to the student network so that the student network can predict a marker point accurately and quickly. The control algorithm is constructed based on the integral-differential model, and the predicted marker point is converted into lateral control commands of a vehicle. Through the experimental analysis of the complexity of the model, prediction accuracy of the marker point, and actual vehicle deployment effect, it is verified that the proposed model can control a vehicle to drive accurately and uniformly along a lane line trajectory.
Simulation validation based on emission coil of three-axis square Helmholtz magnetic source
Authors: Duan Qingming , Zou Bofeng , Zhang Ruju , Song Yuxin , Zhao Hu , Zhang Ruipeng
Published: August 2023

In electromagnetic detection, the received signal strength is largely determined by the transmitter’s signal strength. Therefore, it is necessary to select and design the transmitting coil to meet the requirements of the electromagnetic launching system. To obtain better-transmitting coils, Maxwell is used to establishing square and toroidal coil models for calculation and compare magnetic field intensity and uniformity. To cope with electromagnetic exploration in a complex environment, the electromagnetic field model of the three-axis toroidal coil and square Helmholtz coil is established. The magnetic field simulation results verify that the three-axis square Helmholtz coil has higher emission field intensity under the same excitation condition, which is suitable for electromagnetic exploration.
Application and Error Analysis of Differential Sampling for AC Power Measurement based on Quantum Voltage
Authors: Bai JingFen , Meng Jing , Yang YuBo , Duan MeiMei
Published: August 2023

The quantum voltage standard based on the Josephson effect has been applied in AC power measurement. Differential sampling is the most promising method for measuring AC signals based on quantum technology. In this paper, we developed an AC power measurement system based on differential sampling and analyzed the system error sources through simulations and experiments. The system error comes from the sampling rate, step number of stepped waves, phase difference, and sampling time. The traceability of power to quantum voltage using differential sampling technology was achieved with an uncertainty of 10-6.
A Novel Pulse Excitation Circuit Model and Analysis of Its Magnetic Induction Advantages
Authors: Li Zhi Chao , Zhang Chun Guang , Liu Jia Rui , Chu Shuai , Gong Ying Jiao , Geng Wei
Published: August 2023

In this paper, we discuss the excitation module in the magnetic induction system. First, we start from the traditional sinusoidal input resonant excitation circuit and give the frequency domain equation of its excitation current. Then, we propose a new module based on pulse excitation and give the corresponding excitation equation in the frequency domain. After that, we deduce the mathematical model of excitation gain of new and old modules using application and technology and finally obtain intuitive mathematical analysis graphics for engineering promotion.
The Grinding Parameter Optimization under the Carbon Benefit Objective
Authors: Tian Yingquan , Yin Ruixue
Published: August 2023

Grinding is a high carbon emission process in processing technology. To improve the energy efficiency of the grinding process and reduce the carbon emissions and costs of the grinding process, the concept of carbon efficiency is proposed. The study takes the maximisation of carbon benefit in the grinding process as the optimization objective. The linear speed of the grinding wheel, the feed speed of the workpiece and the radial feed speed of the grinding wheel are taken as the optimization variables. Considering the grinding performance of the grinding wheel, taking the performance of the machine tool and the machining requirements of the workpiece as constraints, a multi-objective optimization model of the grinding process is established. The model is optimized by a genetic algorithm, and the effectiveness of this method is verified by a case.
Long-distance intelligent liquid supply for coal mining faces based on liquid demand prediction
Authors: Li Ran , Wei Wenshu , Lai Yuehua , Wang Dalong , Liu Bo , Wang Tongcheng
Published: August 2023

The coal mine pump station liquid supply system adapts to changes in the main pressure for supply, but under conditions of long-distance liquid supply beyond 2000 m, there is a problem with the difficult system response to the hydraulic support liquid demand, resulting in significant pressure fluctuations in the hydraulic system and serious performance degradation of the supply system. To solve this problem, a long-distance intelligent liquid supply method based on liquid demand prediction for coal mining faces is proposed to ensure stable liquid supply. The method integrates parameters such as the mining machine’s position, the hydraulic support’s column pressure before and after the mining machine, the forward travel distance, and action codes to construct a feature vector. Based on the Transformer Model, a Liquid Demand Prediction Model for hydraulic support is established. Attention mechanisms are combined to solve the problem of time prediction for long sequences. The model is validated using real measured data from a hydraulic system in a coal mine, and the experimental results show that the model can accurately predict liquid demand and achieve long-distance intelligent liquid supply for coal mining faced by combining pump station control strategies.
Three-level ANPC rectifier loss calculation and balance control method
Authors: Ying Zi
Published: August 2023

Traditional three-level neutral-point clamped converter has the problem of the uneven loss distribution, which restricts the increase of converter capacity. Three-level active neutral-point clamped (3L-ANPC) converter can reduce the imbalance of power device loss distribution. At present, three traditional SPWM modulation strategies are used in single-phase three-level ANPC modulation. Considering the loss distribution, it is generally required to input the current and voltage sampling values in real-time and calculate the temperature of the switching device online for control or collect the temperature of the switching device in real-time for feedback control, which is more complicated to realize. This paper proposes a modulation scheme based on two carrier cycles, combined with traditional SPWM1 and 2, to analyze the switching conditions and loss characteristics of each switching device in this scheme. The simulation of a single-phase three-level ANPC rectifier was built, and the experiment was carried out on the Yuankuan HIL semi-physical platform. The results show that this scheme is simple, easy to implement, and can effectively reduce the loss distribution imbalance.
Ocean–atmosphere circulation coherences associated with temperature increase in Pakistan
Authors: Hussain Azfar , Hussain Ishtiaq , Ali Shaukat , Ullah Waheed , Rezaei Abolfazl , Ali Shaukat , Ullah Safi , Abbas Haider , Manzoom Asima , Zhou Jinxing , Cao Jianhua
Published: August 2023

In recent decades, temperature variations have significantly affected the ecosystem and human livelihood in Pakistan. The wavelet analysis is employed to identify the associations between regional temperature change and global teleconnections, i.e. Atlantic Multidecadal Oscillation (AMO), Arctic Oscillation (AO), North Atlantic Oscillation (NAO), El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Tropical Northern Atlantic Index (TNA), Pacific/North American Index (PNA), North Pacific Pattern (NP), Western Pacific Index (WP), and Western Hemisphere Warm Pool (WHWP). This paper first uses monotonic modified Mann–Kendall and Sen’s slope estimator to compute the temperature changes in Pakistan and its homogenous climatic regions during 1960–2020. It is found that the temperature in Pakistan has increased significantly at 0.23 °C dec−1 in the last 62 years, which is also higher than the global average increase. This increase is more evident in region IV and V in spring at 0.63 and 0.43 °C dec−1 respectively, followed by summer and autumn. Temperature changes in Pakistan and its sub-regions are mainly associated with NP, WP and WHWP with higher mean significant coherences. Overall, temperature changes are significantly influenced by multiple interactions of global teleconnections, and these combinations indicate that the integrated influence of teleconnections can better explain the regional temperature changes. The teleconnections with broader significant influence over Pakistan are NP + WP + WHWP, followed by Pacific-based (ENSO, PDO, and PNA), and Atlantic-based (AMO, AO, and NAO) indices as revealed by the mean significant coherences of 0.82, 0.82 and 0.72 respectively. Annually, AMO, TNA and WHWP showed significant correlation with higher magnitudes of 0.44, 0.42 and 0.20 respectively, indicating the modulation effect of these teleconnections on temperature changes over Pakistan. The combined impacts from the various teleconnections represent a considerable advancement in the accuracy of significant temperature variations over the country. These findings have significant implications for policymakers in terms of better planning and policies in light of climate change as well as atmospheric circulation variability.
Classicality of single quantum particles in curved spacetime through the hydrodynamical reformulation of quantum mechanics
Authors: Shushi Tomer
Published: August 2023

Single-particle physics focuses on the behavior and properties of individual particles, providing insight into the building blocks of quantum mechanics. The theory of quantum particles in curved spacetime has been getting attention in recent years for gaining a deeper understanding of the relationship between quantum mechanics and general relativity, the two pillars of modern physics. In this note, we show how single quantum particles can obtain classical behavior. In particular, for a quantum particle that follows the Klein–Gordon equation in curved spacetime in the presence of external potential, we show that when the amplitude of its wavefunction follows the Klein–Gordon equation with an arbitrary effective mass, empty curved spacetime, but with the same curved geometry appearing in the original Klein–Gordon equation of the wavefunction, the quantum force of the particle vanishes, providing a classical description of the quantum particle using a system of coupled classical equations. The result relies on the Madelung hydrodynamical reformulation of quantum mechanics. Understanding how quantum systems transition to a classical behavior is a long-standing challenge in mesoscopic physics, with important implications for a wide range of applications, from quantum computing to condensed matter physics. The result provides a fresh perspective on the relations between quantum and classical effects in curved spacetime.
Numerical Modelling of River Training Work: A review
Authors: Jaafar Qusay N , Sayl Khamis N , Kamel Ammar H
Published: August 2023

The construction of river training structures has a local influence on hydraulic and sediment regimes. River training is simply to modify the dimensions and patterns of channels, bars, and pools. Many scientists have applied and developed methods to identify suitable techniques for river training. In this paper 60 scientific papers were reviewed, and through this review, the researchers were divided according to the method of using the model and according to the problem that the researcher addressed, as 22% of the researchers tended to solve the sediment problem using the HEC-RAS model, and 45% of the researchers tended to solve the problem floods using the HEC- RAS model, as well as 23% of the researchers tended to refine the river section, while the last part of the researchers, who accounted for 10%, worked to solve the navigation problem by increasing the depth, and the most used model was obtained by the researchers, which is HEC- RAS, and reached. The percentage of researchers who used the model is 93%.
A Salt Tolerant Native plants as a Solution for Mobile Sand and Dust in Kuwait
Authors: Al-Dousari Ali , Madouh Tareq , Alrawi Mohamed , Alyaqout Abdullatif , Ahmed Modi , Al-Dousari Noor , Al-Saleh Abeer , William Teena
Published: August 2023

In this study, a coastal research site north of Kuwait Bay faces sand encroachment, floods, and wave erosion. The plantation project’s infrastructure was improved by fencing 1.2 km2 with barbed wire. The heavily deteriorated environment has coppice dunes of Nitraria retusa and Lycium shawii around single, double, or triple plants. To manage mobile sand and dust and protect the research centre, 21,500 Nitraria and Lycium were planted and irrigated with brackish water (around 7000 TDS). In order to aerodynamically shift and/or trap mobile aeolian sediments, the vegetation was planted in a V-shape facing the north-westerly wind. A closer gap (about 1m between plants) on the side facing the primary wind and widened toward the inner edges of the gated area controls mobile sand and dust. This projected design stabilizes the soil, protects against floods and wave erosion, enhances flora and animals, and controls aeolian activity. Mobile sand and dust yearly rates in the downwind traps were reduced by 94% and 64.5%, respectively. Native vegetation can control mobile sand and dust, according to this. Such systems can be more efficient with proper design and plant spacing.
Flow Coefficient Determination in Catchment Based on Analysis of Temperature and Wind Speed Data Using the Fuzzy SMRGT Method
Authors: Gunal Ayse Y , Mehdi Ruya
Published: August 2023

In engineering hydrology, calculating the flow coefficient is a crucial step. The flow coefficient calculation is necessary for directing the rational profiteering of water resources, improving the overall efficiency of water resource utilization, and minimizing the effect of catastrophic events. By precisely determining the flow coefficient, which is the most influential factor in flood flow, the current issues will be mitigated substantially. Various techniques are available in the existing literature for modelling flow coefficient. Most of them, however, rely on black-box approaches that are not generalizable. Therefore, this paper applied an intelligent model based on a fuzzy logic system called the Simple Membership Function and Fuzzy Rules Generation Technique (SMRGT). The new technique considers the physical cause-effect relationship and is intended to aid individuals who struggle to choose the number, form, and logic of membership functions and fuzzy rules in any fuzzy set. The study area’s temperature and wind speed data were incorporated into the SMRGT model’s input variables. The output was the flow coefficient. The prediction made by the model was validated against observational data. The comparison relies on numerous statistics and errors. The results indicated that the SMRGT model predicts the flow coefficient extraordinarily well and is an excellent method for generating membership functions and fuzzy rules.
Application of Weap Model for Managing Water Resources in Iraq: A Review
Authors: Hamdi Aya A , Abdulhameed Isam M , Mawlood Ibtihal A
Published: August 2023

Due to the construction of dams in upstream countries and the usage of surface irrigation systems, Iraq has been experiencing a water shortage. Due to population increase and the expansion of the industrial and agricultural sectors, the country is having difficulty keeping up with the rising demand for water. Many previous studies carried out to optimize the water resources management in Iraq over the two decades using Water Evaluation and Planning (WEAP) modeling considering various aspects and different water resources throughout Iraq provinces. This study aims to find out if the WEAP modeling is reliable to optimize water resources management, fourteen previous studies were reviewed to figure out the fields they focused on, the study limitations, and the obtained results. It was found that the WEAP model is reliable for assessing, planning, and optimization of water resources management.
Determination of Radon Radiation Concentration in Groundwater for Some Wells of Baghdad City
Authors: Mohammed Amer A , Nadaand Kamal B , Falih Ali H , Jassem Ali A
Published: August 2023

The Radon level was measured in (17) groundwater samples collected from Baghdad city/ Iraq and two samples from Tigris and Dyala River. The measurements were performed by RAD7 an electronic radon detector manufactured by Durridge Company Inc. The concentrations of radon (226Ra) ranged from 0.3 to 2 (Bq/L). Radon concentrations from all the villages/towns were well below the was lower than WHO and EPA standard limits recommended by USEPA, UNSCEAR, EU Council and WHO. The total annual effective doses ranges from 1.64to 10.95 μSv.y-1 were less than 0.1mSv.y-1 which Recommended by the World Health Organization (WHO). The study also examined the relationship between the total dissolved solids (TDS) and the concentration of Radon-222 and it shows the absence of any linear relationship between the variables and concentrations Radon.
Evaluation of the Efficiency of the Wastewater Treatment Plant in the Women’s and Children’s Hospital in Ramadi, Anbar, Iraq
Authors: Abdul Karim Muhammad Q , Mahmood Bashar A
Published: August 2023

The current study was conducted to evaluate the efficiency of the wastewater treatment station in the Women’s and Children’s Hospital in the city of Ramadi. Samples were collected from the treatment plant (water entering the station and treated water) during the two study seasons (summer and winter). As some physical, chemical and biological characteristics of the water entering the station and the treated water were studied to find out the efficiency of this station. It included the physical properties (temperature and conductivity), while the chemical properties included (pH, chloride, total hardness, nitrates, and COD, Oils, greases and dissolved oxygen). Biological characteristics include the biological requirement for oxygen. As it was noted that the efficiency of the station in getting rid of the conductivity is 18.38the chloride is 6.79%, the total hardness is 55.58%, the nitrates are 26.3%, and the COD is 30.6%, while the efficiency of the station for the disposal of oils and greases was 40.5% and BOD 49.23%,. The results of the study showed that the use of the water coming out of the station for irrigation and drinking purposes is not valid because some of the determinants exceeded the permissible limit.
Assessing the impact of very large volcanic eruptions on the risk of extreme climate events
Authors: Freychet Nicolas , Schurer Andrew P , Ballinger Andrew P , Suarez-Gutierrez Laura , Timmreck Claudia
Published: August 2023

Very large volcanic eruptions have substantial impacts on the climate, causing global cooling and major changes to the hydrological cycle. While most studies have focused on changes to mean climate, here we use a large ensemble to assess the impact on extreme climate for three years following tropical and extratropical eruptions of different sulfur emission strength. We focus on the impact of an extremely large eruption, injecting 40 Tg sulfur into the stratosphere, which could be expected to occur approximately twice a millennium. Our findings show that the eruption would have a profound effect on large areas of the globe, resulting in extremely rare drought events that under normal circumstances would occur once every century becoming very likely. Several regions such as West Africa, South and East Asia and the Maritime continent are particularly affected with the expected climate shifting well outside the usual range, by up to five standard deviations. These results have important consequences as they indicate that a severe drought in multiple breadbasket regions should be expected following a large eruption. The risk of heavy rainfall tends to decrease over the same regions but by a reduced amount, heatwaves become extremely rare, however the chance of extreme Winter cold surges do not increase by a corresponding amount, since widespread parts of the Northern Hemisphere display a winter warming. Our results show that the location of the eruption is crucial for the change in extremes, with overall changes larger for a Northern Hemisphere eruption than a tropical and Southern Hemisphere eruption, although there is a regional dependency. Simulations of different eruptions with similar forcing distributions but with different sizes are consistent with a linear relationship, however for smaller eruptions the internal variability tends to become dominant and the effect on extreme climate less detectable.
Stronger Arctic amplification produced by decreasing, not increasing, CO2 concentrations
Authors: Zhou Shih-Ni , Liang Yu-Chiao , Mitevski Ivan , Polvani Lorenzo M
Published: August 2023

Arctic amplification (AA), referring to the phenomenon of amplified warming in the Arctic compared to the warming in the rest of the globe, is generally attributed to the increasing concentrations of carbon dioxide (CO2) in the atmosphere. However, little attention has been paid to the mechanisms and quantitative variations of AA under decreasing levels of CO2, when cooling where the Arctic region is considerably larger than over the rest of the planet. Analyzing climate model experiments forced with a wide range of CO2 concentrations (from 1/8× to 8×CO2, with respect to preindustrial levels), we show that AA indeed occurs under decreasing CO2 concentrations, and it is stronger than AA under increasing CO2 concentrations. Feedback analysis reveals that the Planck, lapse-rate, and albedo feedbacks are the main contributors to producing AAs forced by CO2 increase and decrease, but the stronger lapse-rate feedback associated with decreasing CO2 level gives rise to stronger AA. We further find that the increasing CO2 concentrations delay the peak month of AA from November to December or January, depending on the forcing strength. In contrast, decreasing CO2 levels cannot shift the peak of AA earlier than October, as a consequence of the maximum sea-ice increase in September which is independent of forcing strength. Such seasonality changes are also presented in the lapse-rate feedback, but do not appear in other feedbacks nor in the atmospheric and oceanic heat transport processeses. Our results highlight the strongly asymmetric responses of AA, as evidenced by the different changes in its intensity and seasonality, to the increasing and decreasing CO2 concentrations. These findings have significant implications for understanding how carbon removal could impact the Arctic climate, ecosystems, and socio-economic activities.
On the unique ergodicity for a class of 2 dimensional stochastic wave equations
Authors: Forlano Justin , Tolomeo Leonardo
Published: August 2023

We study the global-in-time dynamics for a stochastic semilinear wave equation with cubic defocusing nonlinearity and additive noise, posed on the

2
2

-dimensional torus. The noise is taken to be slightly more regular than space-time white noise. In this setting, we show existence and uniqueness of an invariant measure for the Markov semigroup generated by the flow over an appropriately chosen Banach space. This extends a result of the second author [Comm. Math. Phys. 377 (2020), pp. 1311–1347] to a situation where the invariant measure is not explicitly known.
Evidence of kinesin motors involved in stable kinetochore assembly during early meiosis
Authors: Shah Seema , Mittal Priyanka , Kumar Deepanshu , Mittal Anjani , Ghosh Santanu K.
Published: August 2023

During mitosis, the budding yeast, kinetochores remain attached to microtubules, except for a brief period during S phase. Sister-kinetochores separate into two clusters (bilobed organization) upon stable end-on attachment to microtubules emanating from opposite spindle poles. However, in meiosis, the outer kinetochore protein (Ndc80) reassembles at the centromeres much later after prophase I, establishing new kinetochore-microtubule attachments. Perhaps due to this, despite homolog bi-orientation, we observed that the Ndc80 are linearly dispersed between spindle poles during metaphase I of meiosis. The presence of end-on attachment marker Dam1 as a cluster near each pole suggests one of the other possibilities that the pole-proximal and pole-distal kinetochores are attached end-on and laterally to the microtubules, respectively. Colocalization studies of kinetochores and kinesin motors suggest that budding yeast kinesin 5, Cin8, and Kip1 perhaps localize to the end-on attached kinetochores while kinesin 8 and Kip3 resides at all the kinetochores. Our findings, including kinesin 5 and Ndc80 coappearance after prophase I and reduced Ndc80 levels in cin8 null mutant, suggest that kinesin motors are crucial for kinetochore reassembly and stability during early meiosis. Thus, this work reports yet another meiosis specific function of kinesin motors.
Modeling Risk Factors for Intraindividual Variability: A Mixed-Effects Beta-Binomial Model Applied to Cognitive Function in Older People in the English Longitudinal Study of Ageing
Authors: Parker Richard M A , Tilling Kate , Terrera Graciela Muniz , Barrett Jessica K
Published: August 2023

Cognitive functioning in older age profoundly impacts quality of life and health. While most research on cognition in older age has focused on mean levels, intraindividual variability (IIV) around this may have risk factors and outcomes independent of the mean value. Investigating risk factors associated with IIV has typically involved deriving a summary statistic for each person from residual error around a fitted mean. However, this ignores uncertainty in the estimates, prohibits exploring associations with time-varying factors, and is biased by floor/ceiling effects. To address this, we propose a mixed-effects location scale beta-binomial model for estimating average probability and IIV in a word recall test in the English Longitudinal Study of Ageing. After adjusting for mean performance, an analysis of 9,873 individuals across 7 (mean = 3.4) waves (2002–2015) found IIV to be greater at older ages, with lower education, in females, with more difficulties in activities of daily living, in later birth cohorts, and when interviewers recorded issues potentially affecting test performance. Our study introduces a novel method for identifying groups with greater IIV in bounded discrete outcomes. Our findings have implications for daily functioning and care, and further work is needed to identify the impact for future health outcomes.
Implementing and evaluating a diversity, equity, and inclusion resident recruitment strategy
Authors: Quiroga Lauren C , Starosta Kate , Kelley Lindsey R
Published: August 2023

Purpose

A recruitment strategy was designed to increase the racial diversity of applicants to the postgraduate year 1 pharmacy program at University of Michigan Health, Michigan Medicine (MM). This article describes MM’s diversity, equity, and inclusion (DEI) residency recruitment approach, from conceptualization through implementation, and includes an evaluation of its effectiveness.

The report of the American Society of Health-System Pharmacists (ASHP) Task Force on Racial Diversity, Equity, and Inclusion, published in January 2021, provided a foundation for our recruitment approach. The approach consisted of establishing a residency DEI subcommittee, conducting outreach to under-represented students, and reducing bias in the process by amending the application screening rubric. The combination of these efforts resulted in a 5% increase in applicants from pharmacy schools with a high proportion of under-represented minority students.

Conclusion

A diverse residency program benefits patients, trainees, and the larger healthcare organization. In addition, incorporating DEI into resident recruitment is required by the new ASHP Accreditation Standard for postgraduate pharmacy residency programs effective July 1, 2023. Evaluation of our recruitment efforts demonstrated targeted recruitment as an effective strategy to increase the diversity of a residency program’s applicants. There may be additional barriers not addressed by our interventions to be further explored.
Effectiveness and Safety of Resilient Hyaluronic Acid (RHA) Dermal Fillers for the Correction of Moderate-to-Severe Nasolabial Folds in People of Color: Post Hoc Subgroup Analyses of US Pivotal Clinical Data
Authors: Taylor Susan , Weinkle Susan , Kaufman-Janette Joely , Gallagher Conor J , Kooken Kristie , Brown Jessica
Published: August 2023

Background

People of color (POC) are often underrepresented in clinical studies evaluating the safety and effectiveness of aesthetic products, including hyaluronic acid (HA) fillers, for which there is to date limited clinical data in POC.

Objectives

The aim of this study was to assess the safety and effectiveness of a new line of dynamic resilient HA fillers (RHA; Revance, Nashville, TN) for treating moderate-to-severe nasolabial folds (NLFs) in POC vs non-POC.

Methods

Post hoc subgroup analyses compared the efficacy and safety of POC vs non-POC subjects treated with RHA2, RHA3, or RHA4 for correction of moderate-to-severe NLFs in the pooled per-protocol population (N = 217) in 2 clinical trials. Evaluated population cohorts were classified by Fitzpatrick skin type (FST) (high FST [IV-VI] vs low FST [I-III]) and by subject-reported race (non-White vs White) relative to baseline at 6, 9, 12, and 15 months.

Results

POC consistently showed greater improvement in wrinkle severity and higher responder rates compared with non-POC, which reached statistical significance at several measured time points. Global Aesthetic Improvement Scale scores and subject satisfaction ratings were similar for POC and non-POC and remained high throughout the course of the study. Treatment-related adverse event rates were generally lower for high FSTs vs low FSTs, with no reported cases of keloidal scarring.

Conclusion

The RHA line of dynamic fillers is well tolerated and effective for the correction of moderate-to-severe NLFs in POC and can be confidently used in this important and growing patient population.

See the abstract translated into Hindi, Portuguese, Korean, German, Italian, Arabic, Chinese, and Taiwanese online here: https://doi.org/10.1093/asj/sjad251.

Level of Evidence: 2