Wei Suo, Xuxiang Sun, Weiwei Zhang and Xian Yi
The purpose of this study is to establish a novel airfoil icing prediction model using deep learning with geometrical constraints, called geometrical constraints enhancement…
Abstract
Purpose
The purpose of this study is to establish a novel airfoil icing prediction model using deep learning with geometrical constraints, called geometrical constraints enhancement neural networks, to improve the prediction accuracy compared to the non-geometrical constraints model.
Design/methodology/approach
The model is developed with flight velocity, ambient temperature, liquid water content, median volumetric diameter and icing time taken as inputs and icing thickness given as outputs. To enhance the icing prediction accuracy, the model involves geometrical constraints into the loss function. Then the model is trained according to icing samples of 2D NACA0012 airfoil acquired by numerical simulation.
Findings
The results show that the involvement of geometrical constraints effectively enhances the prediction accuracy of ice shape, by weakening the appearance of fluctuation features. After training, the airfoil icing prediction model can be used for quickly predicting airfoil icing.
Originality/value
This work involves geometrical constraints in airfoil icing prediction model. The proposed model has reasonable capability in the fast assessment of aircraft icing.
Details
Keywords
Lina Qiu, Jin Tian, Weiwei Zhang, Aijun Gong and Weiyu Zhao
Sulfate-reducing bacteria (SRB) are recognized by scholars as the most important class of bacteria leading to corrosion of metal materials. It is important to use the properties…
Abstract
Purpose
Sulfate-reducing bacteria (SRB) are recognized by scholars as the most important class of bacteria leading to corrosion of metal materials. It is important to use the properties of microorganisms to inhibit the growth of SRB in the corrosion protection of metal materials and to protect the environment.
Design/methodology/approach
In this work, the behavior of anaerobic Thiobacillus denitrificans (TDN) intracellular enzyme inhibition of SRB corrosion of EH36 steel was investigated with electrochemical impedance spectroscopy, biological detection technology and X-ray photoelectron spectroscopy.
Findings
Results showed that the SRB crude intracellular enzyme affected the corrosion behavior of EH36 steel greatly and the purified TDN intracellular enzyme inhibits SRB intracellular enzyme corrosion to EH36 steel.
Originality/value
A perfect enzyme activity inhibition mechanism will provide theoretical guidance for the selection and application of anticorrosion microorganisms, which is of scientific significance in the field of microbial anticorrosion research.
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Keywords
Hui Xiao, Xiaotong Guo, Fangzhou Chen, Weiwei Zhang, Hao Liu, Zejian Chen and Jiahao Liu
Traditional nondestructive failure localization techniques are increasingly difficult to meet the requirements of high density and integration of system in package (SIP) devices…
Abstract
Purpose
Traditional nondestructive failure localization techniques are increasingly difficult to meet the requirements of high density and integration of system in package (SIP) devices in terms of resolution and accuracy. Time domain reflection (TDR) is recognized as a novel positioning analysis technology gradually being used in the electronics industry because of the good compatibility, high accuracy and high efficiency. However, there are limited reports focus on the application of TDR technology to SiP devices.
Design/methodology/approach
In this study, the authors used the TDR technique to locate the failure of SiP devices, and the results showed that the TDR technique can accurately locate the cracking of internal solder joints of SiP devices.
Findings
The measured transmission rate of electromagnetic wave signal was 9.56 × 107 m/s in the experimental SiP devices. In addition, the TDR technique successfully located the failure point, which was mainly caused by the cracking of the solder joint at the edge of the SiP device after 1,500 thermal cycles.
Originality/value
TDR technology is creatively applied to SiP device failure location, and quantitative analysis is realized.
Details
Keywords
Lina Qiu, Yanan Mao, Aijun Gong, Weiwei Zhang, Yanqiu Cao and Lu Tong
Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria…
Abstract
Purpose
Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria (SRB). However, no researches about the inhibition are reported according to the authors’ knowledge. The purpose of this paper was to investigate the Inhibition effect of B. bacteriovorus on the corrosion of X70 pipeline steel induced by SRB.
Design/methodology/approach
The effect of B. bacteriovorus on the growth of SRB was studied by measuring the optical density at 600 nm (OD600) and sulfate concentration in culture medium. X70 pipeline steel was used as the test material to investigate the anti-corrosion effect of B. bacteriovorus on SRB by conducting electrochemical analysis (including Tafel polarization curves and electrochemical impendence spectroscopy) and weight loss measurement.
Findings
B. bacteriovorus could inhibit the growth of SRB in culture medium by its predation on SRB, which led to decrease of OD600 value and increase of sulfate concentration. The results of electrochemical analysis indicated that B. bacteriovorus had positive inhibition efficiencies on SRB-induced corrosion of X70 pipeline steel. Moreover, corrosion rate of X70 pipeline steel was declined from 19.17 to 3.75 mg·dm-2·day-1 by the presence of B. bacteriovorus.
Originality/value
This is the first report about using B. bacteriovorus to inhibit the corrosion induced by SRB. Compared to other anti-corrosion methods, the microbial inhibition methods exhibit more considerable application value due to its low cost, high efficiency and non-pollution.
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Keywords
The purpose of this paper is to analyze the reasons that plagiarism in online literature is so hard to control in China, and it will conclude with a clear solution for the future.
Abstract
Purpose
The purpose of this paper is to analyze the reasons that plagiarism in online literature is so hard to control in China, and it will conclude with a clear solution for the future.
Design/methodology/approach
This paper begins its research with the statistics and analysis of plagiarism data and a review of expert interviews regarding online literature publishing. All of these data materials were collected from anti-plagiarism platforms, online literature websites, news report websites and judiciary office websites.
Findings
The paper provides empirical insights into why the plagiarism is so rampant in the publishing of online literature in China. It suggests that the current task of controlling network literature plagiarism is arguably created by the literary production platform, which leads to the problem of the validity of the “self-monitoring model.” In fact, controlling plagiarism must be emphasized by means of external monitoring, because strict supervision and various external punitive measurements for committing plagiarism can force literature-generating platforms to strengthen their own internal monitoring.
Research limitations/implications
Online plagiarism occurs almost constantly, but it rarely results in court cases over copyright because of the lack of a robust copyright ecology in China. This paper considers large amounts of data and cases from self-publishing media platforms.
Practical implications
The paper includes implications for the development of plagiarism management in online literature publishing from the publishing Association, media and government.
Social implications
This paper suggests to online literature users that plagiarism will be controlled when certain active measures against it are taken. The authors hope that this view will promote the development of original online literature.
Originality/value
This paper points out that China must strengthen supervision that comes from outside the online literature generate platforms to control the current rampant plagiarism that occurs on these platforms.
Details
Keywords
Weiwei Zhang, Xianlong Jin and Zhihao Yang
The great magnitude differences between the integral tunnel and its structure details make it impossible to numerically model and analyze the global and local seismic behavior of…
Abstract
Purpose
The great magnitude differences between the integral tunnel and its structure details make it impossible to numerically model and analyze the global and local seismic behavior of large-scale shield tunnels using a unified spatial scale, even with the help of supercomputers. The paper aims to present a combined equivalent & multi-scale simulation method, by which the tunnel's major mechanical properties under seismic loads can be represented by the equivalent model, and the seismic responses of the interested details can be studied efficiently by the coupled multi-scale model.
Design/methodology/approach
The nominal orthotropic material constants of the equivalent tunnel model are inversely determined by fitting the modal characteristics of the equivalent model with the corresponding segmental lining model. The critical sections are selected by comprehensive analyzing of the integral compression/extension and bending loads in the equivalent lining under the seismic shaking and the coupled multi-scale model containing the details of interest is solved by the mixed time explicit integration algorithm.
Findings
The combined equivalent & multi-scale simulation method is an effective and efficient way for seismic analyses of large-scale tunnels. The response of each flexible joint is related to its polar location on the lining ring, and the mixed time integration method can speed-up the calculation process for hybrid FE model with great differences in element sizes.
Originality/value
The orthotropic equivalent assumption is, to the best of the authors’ knowledge, for the first time, used in the 3D simulation of the shield tunnel lining, representing the rigidity discrepancies caused by the structural property.
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Keywords
The purpose of this paper is to assess the recent emergence of contemporary art in Asia from a macro, sociocultural perspective.
Abstract
Purpose
The purpose of this paper is to assess the recent emergence of contemporary art in Asia from a macro, sociocultural perspective.
Design/methodology/approach
This commentary is based on secondary research and recent visits to contemporary art centres in major cities across Asia.
Findings
The author argues that contemporary art in Asia emerges by extension of the Western contemporary art world and suggests that more must be done if Asia is to create a contemporary art world that is both internationally recognised and distinct from its Western precedent.
Originality/value
This commentary debunks the hyperbole surrounding contemporary art in Asia as a regional phenomenon and provides a critical examination of the global (power) dynamics at play.
Details
Keywords
Weiwei Wu, Zhou Liang and Qi Zhang
Nowadays, faced with increasingly dynamic and fierce competition, knowledge is considered to be the core to survive and maintain competitive advantages in both managerial…
Abstract
Purpose
Nowadays, faced with increasingly dynamic and fierce competition, knowledge is considered to be the core to survive and maintain competitive advantages in both managerial practices and academia. Against this background, this study analyzed the influence of technological capabilities (TC) and technology management (TM) on corporate economic performance in the contexts of corporate internal governance mechanisms and external institutional environment from the institutional perspective.
Design/methodology/approach
This study collected data on Chinese publicly listed manufacturing firms in Shenzhen and Shanghai stock markets from 2008 to 2017 and the final data included 3,679 firm-year observations. Ordinary least square regression was used in both regression analysis and robustness tests.
Findings
The empirical results showed that the interaction between TC and TM was positively related to corporate economic performance and both corporate incentives and monitoring mechanisms strengthened this positive relationship; the positive moderating effects of corporate governance were stronger under a more developed corporate external institutional environment.
Originality/value
This research provides a better understanding of the economic effect of TC and TM from the perspective of knowledge integration by indicating that the interaction between TC and TM can enhance corporate economic performance and delimiting the boundaries of this relationship from the institutional perspective.
Details
Keywords
Louisa Ha, Chenjie Zhang and Weiwei Jiang
Low response rates in web surveys and the use of different devices in entering web survey responses are the two main challenges to response quality of web surveys. The purpose of…
Abstract
Purpose
Low response rates in web surveys and the use of different devices in entering web survey responses are the two main challenges to response quality of web surveys. The purpose of this study is to compare the effects of using interviewers to recruit participants in computer-assisted self-administered interviews (CASI) vs computer-assisted personal interviews (CAPI) and smartphones vs computers on participation rate and web survey response quality.
Design/methodology/approach
Two field experiments using two similar media use studies on US college students were conducted to compare response quality in different survey modes and response devices.
Findings
Response quality of computer entry was better than smartphone entry in both studies for open-ended and closed-ended question formats. Device effect was only significant on overall completion rate when interviewers were present.
Practical implications
Survey researchers are given guidance how to conduct online surveys using different devices and choice of question format to maximize survey response quality. The benefits and limitations of using an interviewer to recruit participants and smartphones as web survey response devices are discussed.
Social implications
It shows how computer-assisted self-interviews and smartphones can improve response quality and participation for underprivileged groups.
Originality/value
This is the first study to compare response quality in different question formats between CASI, e-mailed delivered online surveys and CAPI. It demonstrates the importance of human factor in creating sense of obligation to improve response quality.
Details
Keywords
Wei Zhang, Weiwei Lv, Xiaoyan Li and Jiming Yao
In this study, the oxidative degradation performance of indigo wastewater based on electrochemical systems was explored. The decolourization degrees, removal rate of chemical…
Abstract
Purpose
In this study, the oxidative degradation performance of indigo wastewater based on electrochemical systems was explored. The decolourization degrees, removal rate of chemical oxygen demand and biochemical oxygen demand of the indigo wastewater after degradation were evaluated and optimized treatment conditions being obtained.
Design/methodology/approach
The single factor method was first used to select the electrolyte system and electrode materials. Then the response surface analysis based on Box–Behnken Design was chosen to determine the influence of four independent variables such as FeCl3 concentration, NaCl concentration, decolourization time and voltage on the degradation efficiency.
Findings
On the basis of single factor experiment, the electrode material of stainless steel was selected in the double cell, and the indigo wastewater was electrolyzed with FeCl3 and NaCl electrolytes. The process conditions of electrochemical degradation of indigo wastewater were optimized by response surface analysis: the concentration of FeCl3 and NaCl was of 16 and 9 g/L, respectively, with a decolourization time of 50 min, voltage of 10 V and decolourization percentage of 98.94. The maximum removal rate of chemical oxygen demand reached 75.46 per cent. The highest ratio of B/C was 3.77, which was considered to be more biodegradable.
Research limitations/implications
Dyeing wastewater is bringing out more and more pollution problems to the environment. However, there are some shortcomings in traditional technologies such as adsorption and filtration. As a kind of efficient and clean water treatment technology, electrochemical oxidation has been applied to the treatments of various types of wastewater. The decolourization and degradation of indigo wastewater is taken as an example to provide reference for the treatment of wastewater in actual plants.
Practical implications
The developed method provided a simple and practical solution for efficiently degrading indigo wastewater.
Originality/value
The method for the electrochemical oxidation technology was novel and could find numerous applications in the degradation of printing and dyeing wastewater.