bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the spatial distribution characteristics and spatial symbiosis of living supermarkets based on GIS
Authors: Ye Sheng , He Zong , Li Jing , Chen Yang
Published: September 2020

By using the POI data of Gaode, we screened out the life supermarket system, and studied the spatial distribution characteristics of life supermarket system and its spatial symbiosis with the surrounding residential areas. The analysis found that: ① The spatial distribution pattern of Chongqing’s main city supermarkets is consistent with the "multi-center group" urban structure. The development of supermarkets in the main urban area presents the "Matthew Effect", and it still faces several major business districts within the inner ring and its surroundings. Centralized, another university town relies on stable student group demand, showing a new growth direction; ② Convenience stores have relatively homogeneous cluster characteristics, are mainly developed on more mature commercial areas, and have achieved rapid growth in recent years increased by 1.2 times; ③ The overall distribution of imported merchandise stores in the main urban area is small clusters, and the concentration degree in the GuanYinqiao area is the most prominent. Compared with other types, the concentration degree is higher in the Haier Road area near the bonded port area; ④ Living areas with a high degree of compounding of the living supermarket system around the community are mainly distributed within the inner ring and have a high degree of spatial fit with the major business districts. Outside the inner ring, they are mainly distributed in the north of Beibei City, Beibei Old City, Yudong- and Lianglu.
Estimating aboveground biomass of urban trees by high resolution remote sensing image: a case study in Hengqin, Zhuhai, China
Authors: Bai Linze , Shu Yuxuan , Guo Yongxuan
Published: September 2020

Aboveground biomass of trees is the weight of organic matter per unit area of trees. The monitoring and evaluation of aboveground biomass of urban trees is helpful to the construction of garden city. With the development of urbanization and the Continuous urban ecological research, the aboveground biomass of urban trees is getting more important for the study of urban carbon cycle and the construction of ecological city. High resolution remote sensing image, which overcomes the time-consuming and labor-consuming drawbacks of traditional methods, is a data source for estimating the aboveground biomass. In this paper, taking Hengqin New Area, Zhuhai City, Guangdong Province, China as an example, we use the method of object-oriented classification of Worldwire-03 data to extract Hengqin tree area, and analyze 15 feature parameters in remote sensing images including vegetation indexes and texture features. Combined with field measurement and aboveground biomass computation, we set up Geographical Weighted Regression (GWR) model and Random Forest (RF) model for regression. Finally we estimate and discuss the aboveground biomass of trees in Hengqin.
Research and application of solid waste dumping calculation method in criminal cases of environmental pollution caused by illegal dumping of solid waste based on Arcgis
Authors: Ma Ruofan , Cai Bin , Tan Xiao
Published: September 2020

The determination of the amount of solid waste dumping is one of the important links in handling of criminal cases of environmental pollution of illegal dumping of solid waste, and one of the important basis for sentencing of the crime of environmental pollution. This article is based on ArcGIS technology, referring to the commonly used visualization method of earthwork calculation, taking a criminal case of environmental pollution of illegal dumping of solid waste as an example, an irregular triangulation network (TIN) is used to establish a digital elevation model (DEM) of solid waste piles, in order to discuss the application of ArcGIS in the establishment of solid waste heap model, and calculate the amount of solid waste dumping. The results show that using ArcGIS to build a solid waste heap model and calculate the solid waste dumping principle is simple, fast, and can achieve three-dimensional visualization, which is feasible.
Time series analysis of the shadow-eliminated vegetation index (SEVI) and patch density index for the Wuyishan Nature Reserve
Authors: Jiang Hong , Zhou Nian
Published: September 2020

In order to study the vegetation growth changing in the Wuyishan Nature Reserve, the recently proposed shadow-eliminated vegetation index (SEVI) and patch density (PD) were used to evaluate the inter-annual variability of the vegetation growth in the Reserve during 2000-2019. The resultant normalized SEVI sequence eliminated the terrain shadow effect shows an increasing trend overall during 2000-2019. Meanwhile, the series of PD show a decreasing trend with two significant different mean levels of 40.67/km2 during 2000-2011 and 18.69/km2 during 2012-2019. The SEVI and PD had an overall negative correlation with coefficient of determination r
2 = 0.53. The result suggests that the promotion of ecology civilization may contribute to the protection and growth of the nature reserve vegetation.
A simple model for predicting soil infiltration rate for vertical line source irrigation
Authors: Wang Ying , Gong Jiaguo , Fan Yanwei
Published: September 2020

In this study, HYDRUS-2D was used to simulate the soil infiltration rate of vertical line source irrigation (VLSI) under different soil textures and initial water contents, as well as for different lengths, diameters and buried depths of the line source. The soil texture, diameter and length of the line source are the dominant influential factors of the soil infiltration rate of VLSI, whereas the initial water content and buried depth of the line source are less influential. The variation of soil infiltration rate is in accordance with the Philip model. The model parameters, i.e., sorptivity (S) and steady infiltration rate (A), increase as the diameter (D) and length (L) of line source increases. A power function between S and D and L, and one between A and D and L, were established. The exponential value of the power function was determined based on the HYDRUS simulation results, thereby obtaining a simplified estimation model of the soil infiltration rate of VLSI containing D and L. The effectiveness of the simplified model was verified based on a laboratory experiment and currently available research. The MAE (mean absolute error, MAE) is 0.056–0.348, RMSE (Root mean square error, RMSE) is 0.073–0.442, PBIAS (percentage bias, PBIAS) is 1.642 – 2.893, and NSE (Nash-Sutcliffe efficiency coefficient, NSE) is close to 1 (NSE⩾0.973), indicating that the model has a high accuracy and can therefore be used for estimating the soil infiltration rate of VLSI. The simplified estimation model established in this study has only two undetermined parameters that can be obtained based on only one set of experimental data, simplifying the experimental scheme and improving the work efficiency.
The effects of urban park on residents’ health: an empirical study based on Tangxi River Park in Hefei
Authors: Wang Zhipeng , Zhang Chengyong , Chen Yawen , Liu Xiangfeng , Guo Jianghui
Published: September 2020

As an important way for urban residents to access nature environment, urban park has a certain degree of impact on the health of the population. In this study, Tangxihe Park in Hefei City was used as the research site, and the impact of urban parks on population health was quantitatively studied by analyzing the demographic characteristics, physical and mental health of park users, and park satisfaction. The results show that the quality of overall environment, green space and activity facilities of the park have a positive effect on improving the physical and mental health of the residents, the time of residents spending in the park have a positive effect on their physical and mental health, the longer of the residents spending in the park, the higher of the health benefits they received. Physical health regression analysis showed that residents received better physical health benefits by using the park between 6am to 9am compared to those entering the park between 12pm to 14pm and 14pm to 18pm. Mental health regression analysis showed that residents entering the park between 14pm to 18pm received better mental health benefits than those entering the park between 6am to 9am. The research results verify the specific health effects of urban parks in the context of Chinese demographic and geographic background, and enrich the theoretical content on the health benefits of urban parks in different regional contexts.
Research on UAV Large Scale Mapping and its elevation fitting
Authors: Lu Rongshan , Yang Xianli
Published: September 2020

Due to the influence of the external environment and the limitation of data processing methods, the accuracy of the unmanned aerial vehicle (UAV) aerial photogrammetry needs further studies in the aspect of mapping large-scale topographic maps. In order to verify whether the measurement accuracy of the UAV aerial photography system meets the requirements of large-scale topographic maps, this paper conducts an accuracy test on a topographic map, using the surface fitting model, the plane fitting model, quadratic surface fitting and polyhedral function method fitting based on field measured data. The fitting of four models to the elevation points by the combined polyhedral function method. The elevation difference between the flat area and the mountain area was corrected, and the elevation accuracy of the four methods was compared. This paper shows that in flat areas the elevation accuracy of the surface fitting model is better than the plane fitting model, quadratic surface fitting, and polyhedral function method fitting. In the mountainous region, the elevation accuracy of the quadratic surface fitting model is better than that of the plane fitting model, surface fitting model, and polyhedral function method.
Analysis and numerical simulation of the limiting factors of algal blooms in Qiantang River estuary
Authors: Li Ruohua , Pan Cunhong , Ge Can , Wu Xiuguang
Published: September 2020

Algal blooms generally occur in lakes and reservoirs rather than macro-tidal estuary. However, algal blooms repeated in the Qiantang River estuary, a typical macro-tidal estuary, which has seriously influenced the aquatic environment and water supply in Hangzhou. A coupled hydrodynamic-ecological model was established to explore controlling factors of algal blooms in Qiantang River estuary. Environmental variables were carried to study algal growth in which nutrients, water temperature and river runoff affect algal growth strongly in Qiantang River estuary according to the modeling. High nutrient concentration and temperature promote algal growth, and river runoff inversely. Substantially reducing on nutrient inputs is required to mitigate algal blooms due to high nutrient background concentration in the estuary, among which phosphorus reduce is more effective than nitrogen. In addition, more water should be discharged from the upstream reservoirs to suppress algal blooms in the drinking water source area of Hangzhou in summer.
From sponge city to sponge watershed: addressing comprehensive water issues through an innovative framework
Authors: Xue Fei , Wang Jian , Huang Yilong , Jing Ruiying , Lu Qiaohui
Published: September 2020

This paper advocates a shift for Sponge City construction from urban scale towards the watershed scale through strengthening the ecosystem services at a holistic perspective. An innovative framework has been established to address integrated solutions for comprehensive water issues. It enclosed with water resilience pattern, water resource pattern, water treatment pattern, water ecology pattern, waterscape pattern, and LID (low-impact-development) transportation pattern. Specifically, water resilience pattern and water resource pattern deal with the livelihood issues of urban population; water treatment pattern and water ecology pattern provide a sustainable basis through ecological and technical approaches in the context of urban agglomeration. Besides, the waterscape pattern and LID transportation pattern correlated grey infrastructure with green infrastructure, which helps to optimize the quality of urban development and minimize the intervention on the watershed ecosystem. The analyses and discourses from this study identify significant methodological implications to shift the sponge city practice from the urban context towards nature context. The prominent contribution is to optimize the regulation and support service of the watershed ecosystem and promote a healthier environment for people and wildlife living in the watershed.
Stability analysis of offshore wind power monopile foundation under wind load
Authors: Jin Jianli , Hu Cong
Published: September 2020

Based on the calculus and blade element theory, the formulas for calculating wind load on the blade of offshore wind turbine are deduced. The time history curve and wind speed time history curve, power spectrum and wind load of wind turbines are simulated by using MATLAB software with the derived formulas and wind observation data of London Array Wind Farm. Based on the above analysis results, the stability of offshore wind power monopile foundation structures under wind loads is analyzed and studied by using ABAQUS finite element software. It is concluded that the structural stability and ultimate load of offshore wind power structures under horizontal, lower bound and ultimate loads are the same. With the increase of internal friction angle, the shakedown load and ultimate load increase gradually with the increase of pile foundation length.
The application of TOUGHREACT in the field of energy and environment
Authors: Li Lian , Wu Yahong , Chong Shan , Wen Qingzhi
Published: September 2020

TOUGHREACT has been widely used as a chemical reaction simulation program for non-isothermal multiphase flow in pore and fracture media. By analyzing the comprehensive research results, the application status of TOUGHREACT in CO2 geological storage, geothermal energy development, nuclear waste disposal, mineral recovery and silica fouling and environmental pollution remediation are summarized. Finally, the future development trend of TOUGHREACT is also analyzed. It can be used as a reference for the future application of TOUGHREACT in the field of energy and environment.
Geochemistry characteristics and emplacement mechanism of the Cenozoic magma in Baoxingchang area, Yunnan Province, SW China
Authors: Dao Yan , Jian Long , Zhang Yourong , Xiao Gaoqiang , Xu Shengchao
Published: September 2020

Alkali-rich intrusions associated with Cu-Mo mineralization in Baoxingchang district, displaying both felsic and mafic rock series, can be: divided into four evolution stages. LA-ICP-MS zircon U-Pb ages of the four stages intrusions 36.5∼34.6Ma, 38.0∼33.5Ma, 36.0∼34.5Ma and 34.0Ma, respectively. All the studied rocks have similar magma sources and tectonic setting. The εHf(t) values indicate that they were reworked by ancient lithospheric mantle and crustal materials via subduction. Formation of the alkaline-rich intrusions in Baoxingchang area may be involved in the processes of partial melting of mantle rocks, crust-mantle materials and fractional crystallization. It appears an increasing tendency from felsic intrusions, to enclaves and then to early-stage lamprophyre to late-stage lamprophyre.
Comparative analysis of strain parameter acquisition based on Cave strain and GPS observation
Authors: Hu Leyin , Lv Taiwen , Yan Rui , Fan Zhiyong , Xu Bin
Published: September 2020

A set of three-component extensometers are installed on the Xibozi Seismic Station in Yanqing District, Beijing. The layout of the extensometers is an isosceles triangle, and the observation is the amount of expansion and contraction of each side, which is then converted into the strain value of each side. In this paper, the regional crustal strain parameters were calculated based on the observations of the extensometers and the continuous GPS observations around Xibozi Sesimic Staion. From two aspects of observation at the same site and different scales, the ground strain information reflected by the two observation methods is compared and analyzed. From the strain parameters calculated by a single point (extensometers) and the strain parameters calculated by the triangular surface observation (GPS) with different specifications, the overall Beijing area is in the context of tensile strain. However, there is a gap of several orders of magnitude between the two results, which may be related to the artificial operation of the pre-processes such as zero drift and step removal of the instrument’s strain observation data.
Micro Dry Wire EDM: Kerf Investigation using Response Surface Methodology
Authors: Ali Mohammad Yeakub , Banu Asfana , Rahman Mohamed Abdul , Al Hazza Muataz Hazza , Khan Chowdhury Ahmed Ghalib
Published: September 2020

Dry electrical discharge machining (DEDM) is an environmentally friendly and green machining process where it uses gas as the dielectric fluid instead of liquid. It is an alternative to the conventional electrical discharge machining (EDM) process. However, kerf variation remains as a critical issue in micro dry wire EDM (µDWEDM) process. Therefore, the objective of this research is to investigate kerf in µDWEDM using response surface methodology (RSM). The experimental investigation was perform using an integrated multi process machine tool, DT 110 (Mikrotools Inc., Singapore). Stainless steel (SS304), tungsten wire, and compressed air were used as the workpiece, electrode, and dielectric fluid respectively. Central composite design (CCD), a type of RSM, was used to design the experiment using two controlled parameters which were capacitance and gap voltage. Analysis of variance (ANOVA) was used to analyse the results and to evaluate the adequacy of the developed model. The results were obtained by measuring the kerf using scanning electron microscope (SEM) (JEOL JSM-5600, Japan). An empirical model has been developed, and it was found that both parameters; capacitance and gap voltage have high influence on kerf. The optimum parameters for minimum kerf were found to be 0.1 nF capacitance and 91 V gap voltage. The developed model was found to be adequate since the percentage error was relatively small (≈ 2%).
Non-contact Detection of Delamination in Cu/Al Laminated Plate with Laser Ultrasonic
Authors: Ji Baoping , Zhang Qingdong , Zhang Liyuan , Cao Jianshu , Zhang Boyang
Published: September 2020

In this paper, a non-contact non-destructive inspection method based on laser ultrasonic was proposed for the detection of interface delamination in Cu/Al laminated plates. The finite element model of laser ultrasonic Cu/Al laminated plates were built to analyze the propagation of laser ultrasound in Cu/Al laminated plates and the effects of interface delamination defects on the ultrasonic field distribution. The simulation results were verified by the laser ultrasonic detection system. The C-scan detection results realizes the visual detection of delamination defects, and provides precise information about the composite quality of the Cu/Al laminated plates. Experimental results show that laser ultrasonic technology has great potential for online non-contact detection of Cu/Al laminated plates.
Kinematics of Planar Quabody Mechanism with More Kinematics Bifurcation Positions
Authors: Li C M , Cao H , Liu Q , Liu X
Published: September 2020

Based on multibody dynamics, some definitions of mechanism are defined. The kinematics bifurcation position is a cold researching spot for many many years. It is common in planar quabody mechanisms but has not been paid enough attention to. The kinematics bifurcation position refers to the mechanism position with a pressure angle of 90° of the follower, including the stuck position (dead point). In this paper, a planar quabody mechanism is studied. In a motion cycle, there are three kinematics bifurcation positions in the mechanism. The third derivative of angle to time, angular velocity, angular acceleration of the connecting rod in kinematics bifurcation positions is obtained by solving the kinematics parameters of kinematics bifurcation positions according to L’Hopital’s rule. If the driving body swings in sinusoidal law, the motion of the mechanism is continuous. The kinematics characteristics of the mechanism are independent of the simulation convergence and response bifurcation of nonlinear dynamics. The length of the rocker is 1 m, the length of the connecting rod is 0.5 m, the distance between the track of the slider and the fixed point of the rocker is 0.5 m, and the rocker swings according to the sine law with a period of 9 seconds. The computer simulation shows that the speed and acceleration are continuous and so there is no impact in the kinematics bifurcation positions.
An Approach to Suppress Flow Separation by Plasma Vortex Generator as a Combined Active and Passive Control Mechanism
Authors: Mukut A N M M I , Afroz H M M , Mizunuma H , Hiromichi O
Published: September 2020

Flow control is an important issue in fluid mechanics and aerodynamics as separated flow introduce undesirable impact on overall system performance. Several active and passive techniques have been used to control the flow when necessary. But in passive control techniques, the actuator has to be fixed on the surface so that it can create vortices along streamline to enhance the mixing in the separated region to delay or suppress separation. Among passive flow control system vortex generators (VGs) are generally used but it control the flow with the cost of drag increase. It would be advantageous by combining both active and passive flow techniques together. In this regard plasma actuator (PA, active flow control device) and VGs are combined together with a view to not only suppress the separation but also minimizing the drag that could arise by using conventional passive control techniques. The combination flow control device is named as Plasma Vortex Generator (PVG) which proves its effectiveness to control separation as conventional VGs do but without any drag penalty.
Research on Equivalent Thickness of Oil and Gas Spring Damping Valve
Authors: Chen Yijie , Han Xiaoling , Xiang Lang , Zhao Ning , Dai Jianjian
Published: September 2020

Analytical algorithm for deflection analysis of superimposed throttle plate of oil and gas spring damping valve was studied, the theory of equivalent thickness of superposed valve plates was put forward, it can accurately calculate the equivalent thickness of a single valve plate corresponding to the superimposed valve plate groups, which greatly facilitates engineering calculations. After that, the boundary flow theory was used to derive the flow expression of the gap under the turbulent state. The relationship between the output force and displacement of the oil and gas spring was simulated and analyzed, compared with experimental data, the correctness of the mathematical model was verified.
Study on Calibration Technology and Uncertainty Evaluation of Asphalt Vacuum Decompression Capillary Viscometer
Authors: Liu Chang , Zhou Yishu , Ren Lishuo , Zhang Jinning , Zhu Fenghua
Published: September 2020

60 °C dynamic viscosity is one of the main indexes to evaluate the quality of asphalt products, and its influence on the quality of asphalt pavement is very important. 60 °C dynamic viscosity is usually measured by the asphalt vacuum decompression capillary viscometer (hereinafter referred to as the viscometer). The quality of the viscometer directly affects the test results of the asphalt dynamic viscosity. Therefore, it is urgent to study the detection method of viscometer to ensure the quality of the viscometer and the accuracy of the test results. In this paper, the calibration test method of viscometer is established, and the uncertainty evaluation is carried out, which provides a technical basis for ensuring the accuracy of viscometer.
The King of the New Generation Photovoltaic Technologies——Perovskite Solar Cells & the Opportunities and Challenges
Authors: Chen Qianyu
Published: September 2020

Within the past several decades, photovoltaic technology is an emerging pioneer in the renewable energy field. Driven by the rapid decline in the price of photovoltaic products, the cost of photovoltaic power generation is becoming cheaper or even lower than the cost of thermal power generation. Among various photovoltaic technologies, organic-inorganic hybrid perovskite thin film solar cells are promising candidates for the next generation of solar cells in consideration of their outstanding advantages such as low-cost, easy manufacturing processing and high power conversion efficiencies. Perovskite solar cells stem from dye-sensitized solar cells. Within less than a decade of rigorous research and development in perovskite solar cells, the efficiency is boosted up to 25.2%. Aforementioned high PCE is mainly attributed to outstanding photovoltaic properties such as the long diffusion length of carriers, high optical absorption coefficient, excellent carrier mobility, etc. Meanwhile, the main barriers of commercialization for the perovskite solar cells are the poor stability of the devices, and the possible environmental pollution caused by lead. Herein, we briefly reviewed the opportunities and the challenges of this game changer in photovoltaic field. The development prospective are also discussed.
Similarity Model Development of Spar Floating Wind Turbine for Vibration Experimental Study
Authors: Huang W.Q. , He E.M. , Yang J.J.
Published: September 2020

As the fixed foundation wind turbine no longer meets the design and cost requirements in deep sea power plant, and the offshore floating wind turbine (FOWT) suitable has been developed rapidly. The spar FOWT model is established in ANSYS-AQWA, and the influences of spectral peak frequency and incident angle for irregular waves on the vibration responses of FOWT are studied under five load cases. Under the guidance of similar theory, 1/150 scaled model has been simulated under typical load cases. The results show that the peak frequency of the spectrum has a significant effect on the vibration responses of FOWT, the incident angle also has a slight effect. By comparing the maximum and standard deviation (SD) of the tower top fore-aft displacement (TTDspFA) with the physical model and the experimental model, the minimum errors are 3.60% and 3.56%, respectively. This work will lay a foundation for experimental study on vibration of the floating wind turbine.
Optimization of Aviation Wireless Sensor Network based on Discrete Cuckoo Search Algorithm
Authors: Yang Rui , Xu Mengying , Zhou Jie
Published: September 2020

Aiming at the problems of multiple coverage blind areas, poor monitoring quality, and low utilization of sensor network nodes in aviation wireless sensor networks, a discrete cuckoo search (DCS) is proposed, and an objective coverage optimization function is established. Aiming at the fact that the previous cuckoo search is not suitable for discrete values, the binary code conversion formula is used to perform binary code conversion on the jump path of each position update of Levy flight, which makes the algorithm converge faster and avoids the limitations of local search. In the simulation, the discrete cuckoo search was compared with ant colony optimization (ACO) and particle swarm optimization (PSO). Simulation experiment results show that the proposed discrete cuckoo search (DCS) has a great advantage in convergence speed, more targets are detected, and the target coverage in the aerial wireless sensor network is effectively improved.
Creative Design of Streamline Groove Mechanical Seal Based on TRIZ Theory
Authors: Heshun Wang , Lei Zhou , Liu Xiaoming , Zhang Chening , Wang Zeping , Zhu Weibing
Published: September 2020

In view of the problems of poor stability and large leakage of dynamic pressure non-contact mechanical seals in a specific working environment, through the analysis of the mechanical seal principles and end structure, based on the TRIZ theory, choose the “structure stability”, “adaptability and versatility” as the improve elements, the “harmful emission” and “foreign harmful factors” as the deteriorate elements. The principle numbers of the invention are obtained from the contradiction matrix. According to the principles of the invention, a new type of streamline groove mechanical seal is designed. Through the technology of making groove on the end face, a fluid film with a certain stiffness is obtained, and the end face is sealed. Through improve the stability and adaptability of the mechanical seal operation, it can operate safely and stably in a specific working environment and meet the requirements of the seal.
A Study on the Deep Learning based Prediction of Production Demand by using LSTM under the State of Data Sparsity
Authors: Jung Ho-Seok , Park Sungbum
Published: September 2020

Rapid market condition changes and growing uncertainties require accurate product demand forecasting to reduce the risks of business operations. So far, recurrent neural networks (RNNs) have been introduced as the representative models for forecasting time series data. However, it showed limited performance when learning time pattern occurring over a long period of time. This study performs deep learning-based production forecasting analysis with Long-term short-term memory (LSTM) and dropout algorithm as the alternative for the conventional time series analysis methods and the exponential smoothing method. Our result provides the reference for sales target setting, facility investment and production planning, inventory control, supply chain management, and marketing strategy establishment.
Somatosensory Interaction of the Science Exhibition Based on Flow Theory
Authors: Chao Yin , Yang Chen , Wang Jian-Wei , Shi Ruo-Hao
Published: September 2020

In order to improve the immersion and pleasure of users from science exhibition, a design method based on flow theory is proposed. Based on the flow theory, it proposes to set up clear science goals and sense of substitution for somatosensory interactive science exhibits, to maintain the unity of user skills and task difficulty, to maintain timely and effective feedback, to promote the guidance layer to maintain the continuation of the flow and other design methods, and Use jack simulation software for environment optimization research and analysis. Verification by the flow experience Likert scale proves that this method can greatly increase the probability and duration of the user’s flow state, and effectively compensate for the shortcomings of neglecting the user experience in the design of traditional somatosensory interactive science exhibits. The example proves that the design of the somatosensory interactive science exhibits based on the flow theory can effectively improve the user’s science experience and enhance the user’s immersion and pleasure. This method has good universality.
High-density plasma etching characteristics of aluminum-doped zinc oxide thin films in Cl2/Ar plasma
Authors: Zhang Liting , Joo Young-Hee , Um Doo-Seung , Kim Chang-Il
Published: September 2020

We investigated the etching characteristics of aluminum-doped zinc oxide (AZO) thin films in an adaptively coupled plasma (ACP) system. The dry etching characteristics of AZO films were studied by changing the Cl2/Ar gas mixing ratio, RF power, DC bias voltage. We determined the following optimized process conditions: RF power of 500 W, DC bias voltage of −100 V, process pressure of 15 mTorr. In Cl2/Ar plasma (=50:50%), the maximum etching rate of AZO films is 70.45 nm min−1. The ion composition of Cl2/Ar plasma was determined by optical emission spectrometry (OES). The chemical reactions on the surface of AZO films were analyzed by x-ray photoelectron spectroscopy (XPS).
Electrical conductivity spectra of hepatic tumors reflect hepatocellular carcinoma progression in mice
Authors: Shetty Sachin , U Anushree , Kumar Rajesh , Bharati Sanjay
Published: September 2020

Background: Electrical impedance spectroscopy is a technique which evaluates differences in dielectric properties of tissues for cancer identification. Methods: Murine hepatic cancer model was developed by intraperitoneal administration of N-nitrosodiethylamine to male BALB/c mice. Tumors obtained were evaluated for their conductivity in frequency range of (4 Hz–5 MHz). All tumors were subjected to histopathological grading and parameters such as free spacing, necrosis, and cell density were estimated on histological slides. The status of gap junctions and gap junction intercellular communication (GJIC) were studied using enzyme-linked immunosorbent assay, immunohistochemistry, dye transfer assay, and electron microscopy. Results: Histopathological investigation revealed the presence of moderately to poorly-differentiated hepatocellular carcinoma (HCC) in mice. All types of tumors showed higher electrical conductivity than normal liver tissue in frequency range (4 Hz–1 kHz). However, in frequency range (10 kHz–5 MHz) only poorly-differentiated tumors showed higher conductivity compared to normal tissue. The most prominent findings in moderately-differentiated and poorly-differentiated HCC were increased visible free spaces and necrosis respectively. The status of cell gap junctions were significantly deteriorated in tumors and a corresponding significant reduction in GJIC was also observed. These biological indicators were correlated with electrical conductivity of hepatic tumors. Conclusion: Variations in electrical conductivity spectra of hepatic tumors reflect progression of HCC. General significance: Future studies can be planned to perform hierarchical clustering of dielectric parameters with more number of tumor samples to establish dielectric spectroscopy-based classification or staging of hepatic tumors.
AI could reduce teacher workload
Authors: Perks Simon
Published: September 2020

Researchers at the University of Birmingham have developed an artificial intelligence (AI)-based system that could reduce the amount of time that school and university physics teachers spend marking student assignments.
Charging ahead
Authors: Curtis Susan
Published: September 2020

With electric cars set to enter the mainstream over the next few years, Susan Curtis investigates the new charging solutions that will be needed to power what are effectively large batteries on wheels
Good vibrations
Authors: Andrews David R
Published: September 2020

Without mechanical vibrations, a modern car wouldn’t get far down the road – in fact it wouldn’t start. David R Andrews examines the role of sound and ultrasound in fuel injection and parking sensors
A matter of trust
Authors: Ball Philip
Published: September 2020

What a difference a few months can make. When science historian Naomi Oreskes was writing her latest book Why Trust Science? a large part of the context seemed to be climate change.
Our perilous planet
Authors: Appell David
Published: September 2020

"It's a dangerous world out there," writes Ellen Prager in her latest book Dangerous Earth: What We Wish We Knew About Volcanoes, Hurricanes, Climate Change, Earthquakes, and More
2020 summer quiz - part 1
Authors: Durrani Matin , Rich Caleb
Published: September 2020

After tackling astronomy and laser physics last month, get ready to try these fiendish quantum questions, test your Nobel knowledge, and practise your tune trivia. Answers to both parts of the quiz will be published next month.
X-ray ghost imaging goes energy-selective
Authors: Dumé Isabelle
Published: September 2020

Researchers in China have used a technique known as X-ray ghost imaging (XGI) to obtain spectral images of an object using a single-pixel detector.
Artificial Intelligence–Based Screening for Mycobacteria in Whole-Slide Images of Tissue Samples
Authors: Pantanowitz Liron , Wu Uno , Seigh Lindsey , LoPresti Edmund , Yeh Fang-Cheng , Salgia Payal , Michelow Pamela , Hazelhurst Scott , Chen Wei-Yu , Hartman Douglas , Yeh Chao-Yuan
Published: September 2020

Objectives

This study aimed to develop and validate a deep learning algorithm to screen digitized acid fast–stained (AFS) slides for mycobacteria within tissue sections.

Methods

A total of 441 whole-slide images (WSIs) of AFS tissue material were used to develop a deep learning algorithm. Regions of interest with possible acid-fast bacilli (AFBs) were displayed in a web-based gallery format alongside corresponding WSIs for pathologist review. Artificial intelligence (AI)–assisted analysis of another 138 AFS slides was compared to manual light microscopy and WSI evaluation without AI support.

Results

Algorithm performance showed an area under the curve of 0.960 at the image patch level. More AI-assisted reviews identified AFBs than manual microscopy or WSI examination (P < .001). Sensitivity, negative predictive value, and accuracy were highest for AI-assisted reviews. AI-assisted reviews also had the highest rate of matching the original sign-out diagnosis, were less time-consuming, and were much easier for pathologists to perform (P < .001).

Conclusions

This study reports the successful development and clinical validation of an AI-based digital pathology system to screen for AFBs in anatomic pathology material. AI assistance proved to be more sensitive and accurate, took pathologists less time to screen cases, and was easier to use than either manual microscopy or viewing WSIs.
Variation in cranial asymmetry among the Delphinoidea
Authors: Laeta Maíra , Ruenes Greicy F , Siciliano Salvatore , Oliveira João A , Galatius Anders
Published: September 2020

The remarkable directional cranial asymmetry of odontocete skulls has been proposed to be related to sound production. We investigated the variation in quality and quantity of cranial asymmetry in the superfamily Delphinoidea using geometric morphometrics and then investigated the relationship between asymmetry and aspects of sound production. In the average asymmetric shape, the dorsal aspect of the skull outline and interparietal suture crest were displaced to the right, while the nasal septum, nasal bones and right premaxilla were displaced to the left. The nasal bone, premaxilla and maxilla were all larger on the right side. Three delphinoid families presented similar expressions of asymmetry; however, the magnitude of the asymmetry varied. The Monodontidae showed the greatest magnitude of asymmetry, whereas the Phocoenidae were much less asymmetric. The most speciose family, the Delphinidae, presented a wide spectrum of asymmetry, with globicephalines and lissodelphinines among the most and least asymmetric species, respectively. Generalized linear models explaining the magnitude of asymmetry with characteristics of echolocation clicks, habitat use and size revealed associations with source level, dive depth and centroid size. This supports a relationship between asymmetry and sound production, with more asymmetric species emitting louder sounds. For example, louder clicks would be beneficial for prey detection at longer ranges in deeper waters.
Necessity is the mother of invention and the evolutionary force driving the success of in vitro fertilization
Authors: Bartolucci Alison F , Peluso John J
Published: September 2020

During the last few decades, millions of healthy children have been born with the aid of in vitro fertilization (IVF). This success belies the fact that IVF treatment is comprised of a complex series of interventions starting with a customized control ovarian stimulation protocol. This is followed by the induction of oocyte maturation, the retrieval of mature oocytes and in vitro fertilization, which often involves the microinjection of a single sperm into the oocyte. After fertilization, the resulting embryos are cultured for up to 7 days. The best embryos are transferred into the uterus where the embryo implants and hopefully develops into a healthy child. However, frequently the best embryos are biopsied and frozen. The biopsied cells are analyzed to identify those embryos without chromosomal abnormalities. These embryos are eventually thawed and transferred with pregnancy rates as good if not better than embryos that are not biopsied and transferred in a fresh cycle. Thus, IVF treatment requires the coordinated efforts of physicians, nurses, molecular biologists and embryologists to conduct each of these multifaceted phases in a seamless and flawless manner. Even though complex, IVF treatment may seem routine today, but it was not always the case. In this review the evolution of human IVF is presented as a series of innovations that resolved a technical hurdle in one component of IVF while creating challenges that eventually lead to the next major advancement. This step-by-step evolution in the treatment of human infertility is recounted in this review.
‘We’re not delivering government’s agenda’: The Community Organisers Programme in England
Authors: Fisher Robert
Published: September 2020

Community organising is expanding globally. One example is the Community Organisers Programme in England, initiated by the Cameron coalition government from 2011 to 2015. This qualitative study of the Community Organisers Programme juxtaposes critical theory regarding neoliberalism and state devolution with the experiences of fifteen subjects interviewed in 2014 and 2015. The three cohorts included (i) five recruited, salaried and trained community organisers, (ii) five administrative staff from key social service organisations and government and (iii) five external professionals including leading full-time community organisers and/or academic activists recognised in the overall field. The case study confirms expected outcomes regarding the existing theory on neoliberalism and state incorporation. Nevertheless, the interviews revealed both more nuance in relation to the existing theory and literature as well as some surprises in the Community Organisers Programme, which are potentially instructive for future community organising within and outside of social work. Two were (i) the relative absence of bureaucratic burden from the government and sense of autonomy felt by the community organisers and staff and (ii) the progressive potential of adding public funding of community organising to diversify and expand the funding mix in response to our extraordinarily challenging contemporary context.
Motion Coherence and Luminance Contrast Interact in Driving Visual Gamma-Band Activity
Authors: Pellegrini Franziska , Hawellek David J , Pape Anna-Antonia , Hipp Joerg F , Siegel Markus
Published: September 2020

Synchronized neuronal population activity in the gamma-frequency range (>30 Hz) correlates with the bottom-up drive of various visual features. It has been hypothesized that gamma-band synchronization enhances the gain of neuronal representations, yet evidence remains sparse. We tested a critical prediction of the gain hypothesis, which is that features that drive synchronized gamma-band activity interact super-linearly. To test this prediction, we employed whole-head magnetencephalography in human subjects and investigated if the strength of visual motion (motion coherence) and luminance contrast interact in driving gamma-band activity in visual cortex. We found that gamma-band activity (64–128 Hz) monotonically increased with coherence and contrast, while lower frequency activity (8–32 Hz) decreased with both features. Furthermore, as predicted for a gain mechanism, we found a multiplicative interaction between motion coherence and contrast in their joint drive of gamma-band activity. The lower frequency activity did not show such an interaction. Our findings provide evidence that gamma-band activity acts as a cortical gain mechanism that nonlinearly combines the bottom-up drive of different visual features.
Serotype Patterns of Pneumococcal Disease in Adults Are Correlated With Carriage Patterns in Older Children
Authors: Wyllie Anne L , Warren Joshua L , Regev-Yochay Gili , Givon-Lavi Noga , Dagan Ron , Weinberger Daniel M
Published: September 2020

Background

The importance of specific serotypes causing invasive pneumococcal disease (IPD) differs by age. Data on pneumococcal carriage in different age groups, along with data on serotype-specific invasiveness, could help explain these age-related patterns and their implications for vaccination.

Methods

Using pneumococcal carriage and disease data from Israel, we evaluated the association between serotype-specific IPD in adults and serotype-specific carriage prevalence among children in different age categories, while adjusting for serotype-specific invasiveness. We estimated carriage prevalence using different age groupings that were selected a priori. The Deviance Information Criterion was used to determine which age groupings of carriage data best fit the adult IPD data. Serotype-specific disease patterns were further evaluated by stratifying IPD data by comorbidity status.

Results

The relative frequency of serotypes causing IPD differed between adults and children, and also differed between older and younger adults and between adults with and without comorbidities. Serotypes overrepresented as causes of IPD in adults were more commonly carried in older children compared with younger children. In line with this, the serotype-specific frequency of carriage in older children, rather than infants, best correlated with serotype-specific IPD in adults.

Conclusions

These analyses demonstrate that the serotype patterns in carriage in older children, rather than infants, are best correlated with disease patterns in adults. This might suggest these older children are more influential for disease patterns in adults. These insights could help in optimizing vaccination strategies to reduce disease burden across all ages.
Reduced Influenza B–Specific Postvaccination Antibody Cross-reactivity in the B/Victoria Lineage–Predominant 2019/20 Season
Authors: Xie Hang , Xiang Ruoxuan , Wan Hamilton J , Plant Ewan P , Radvak Peter , Kosikova Martina , Li Xing , Zoueva Olga , Ye Zhiping , Wan Xiu-Feng
Published: September 2020

Background

The influenza activity of the 2019/20 season remained high and widespread in the United States with type B viruses predominating the early season. The majority of B viruses characterized belonged to B/Victoria (B/Vic) lineage and contained a triple deletion of amino acid (aa) 162–164 in hemagglutinin (3DEL). These 3DEL viruses are antigenically distinct from B/Colorado/06/2017 (CO/06)—the B/Vic vaccine component of the 2018/19 and 2019/20 seasons representing the viruses with a double deletion of aa 162–163 in hemagglutinin (2DEL).

Methods

We performed molecular characterization and phylogenetic analysis of circulating B/Vic viruses. We also conducted hemagglutination inhibition (HAI) assay using archived human postvaccination sera collected from healthy subjects administered with different types of 2018/19 or 2019/20 seasonal vaccines. Their HAI cross-reactivity to representative 3DEL viruses was analyzed.

Results

The CO/06-specific human postvaccination sera, after being adjusted for vaccine type, had significantly reduced HAI cross-reactivity toward representative 3DEL viruses, especially the 136E+150K subgroup. The geometric mean titers against 3DEL viruses containing 136E+150K mutations were 1.6-fold lower in all populations (P = .051) and 1.9-fold lower in adults (P = .016) compared with those against the 136E+150N viruses.

Conclusions

Our results indicate that postvaccination antibodies induced by the B/Vic vaccine component of the 2019/20 influenza season had reduced HAI cross-reactivity toward predominant 3DEL viruses in the United States. A close monitoring of the 3DEL 136E+150K subgroup is warranted should this subgroup return and predominate the 2020/21 influenza season.