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A carbon efficiency upgrading method for mechanical machining based on scheduling optimization strategy

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Frontiers of Mechanical Engineering 2020年第2期15卷 338-350页

作者： Shuo ZHU Hua ZHANG Zhigang JIANG Bernard hon Key Laboratory of Metallurgical Equipment and Control Technology(Ministry of Education) Wuhan University of Science and TechnologyWuhan 430081China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering(Ministry of Education) Wuhan University of Science and TechnologyWuhan 430081China Engineering Research Center for Metallurgical Automation and Detecting Technology(Ministry of Education) Wuhan University of Science and TechnologyWuhan 430081China School of Engineering University of LiverpoolLiverpool L693BXUK

Low-carbon manufacturing(LCM)is increasingly being regarded as a new sustainable manufacturing model of carbon emission reduction in the manufacturing *** this paper,a two-stage low-carbon scheduling optimization method of job shop is presented as part of the efforts to implement LCM,which also aims to reduce the processing cost and improve the efficiency of a mechanical machining *** the first stage,a task assignment optimization model is proposed to optimize carbon emissions without jeopardizing the processing efficiency and the profit of a machining ***-dominated sorting genetic algorithm II and technique for order preference by similarity to an ideal solution are then adopted to assign the most suitable batch task of different parts to each *** the second stage,a processing route optimization model is established to plan the processing sequence of different parts for each ***,niche genetic algorithm is utilized to minimize the makespan.A case study on the fabrication of four typical parts of a machine tool is demonstrated to validate the proposed method.

关键词： Low-carbon manufacturing carbon efficiency multi-objective optimization two-stage scheduling job shop

A novel observation points‐based positive‐unlabeled learning algorithm

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1425-1443页

作者： Yulin He Xu Li Manjing Zhang philippe Fournier‐Viger Joshua Zhexue Huang Salman Salloum Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) ShenzhenChina College of Computer Science and Software Engineering Shenzhen UniversityShenzhenChina School of Computing National University of SingaporeSingaporeSingapore

In this study,an observation points‐based positive‐unlabeled learning algorithm(hence called OP‐PUL)is proposed to deal with positive‐unlabeled learning(PUL)tasks by judiciously assigning highly credible labels to unlabeled *** proposed OP‐PUL algorithm has three ***,an observation point classifier ensemble(OPCE)algorithm is constructed to divide unlabeled samples into two categories,which are temporary positive and permanent negative ***,a temporary OPC(TOPC)is trained based on the combination of original positive samples and permanent negative samples and then the permanent positive samples that are correctly classified with TOPC are retained from the temporary positive ***,a permanent OPC(POPC)is finally trained based on the combination of original positive samples,permanent positive samples and permanent negative *** exhaustive experimental evaluation is conducted to validate the feasibility,rationality and effectiveness of the OP‐PUL algorithm,using 30 benchmark PU data *** show that(1)the OP‐PUL algorithm is stable and robust as unlabeled samples and positive samples are increased in unlabeled data sets and(2)the permanent positive samples have a consistent probability distribution with the original positive ***,a statistical analysis reveals that POPC in the OP‐PUL algorithm can yield better PUL performances on the 30 data sets in comparison with four well‐known PUL *** demonstrates that OP‐PUL is a viable algorithm to deal with PUL tasks.

关键词： artificial intelligence datamining,machine learning

Observation points classifier ensemble for high-dimensional imbalanced classification

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CAAI Transactions on Intelligence Technology 2023年第2期8卷 500-517页

作者： Yulin He Xu Li philippe Fournier‐Viger Joshua Zhexue Huang Mianjie Li Salman Salloum College of Computer Science&Software Engineering Shenzhen UniversityShenzhenChina Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen UniversityShenzhenChina Faculty of Information Technology Macao University of Science and TechnologyMacaoChina School of Computing National University of SingaporeSingaporeSingapore

In this paper,an Observation Points Classifier Ensemble(OPCE)algorithm is proposed to deal with High-Dimensional Imbalanced Classification(HDIC)problems based on data processed using the Multi-Dimensional Scaling(MDS)feature extraction ***,dimensionality of the original imbalanced data is reduced using MDS so that distances between any two different samples are preserved as well as ***,a novel OPCE algorithm is applied to classify imbalanced samples by placing optimised observation points in a low-dimensional data ***,optimization of the observation point mappings is carried out to obtain a reliable assessment of the unknown *** experiments have been conducted to evaluate the feasibility,rationality,and effectiveness of the proposed OPCE algorithm using seven benchmark HDIC data *** results show that(1)the OPCE algorithm can be trained faster on low-dimensional imbalanced data than on high-dimensional data;(2)the OPCE algorithm can correctly identify samples as the number of optimised observation points is increased;and(3)statistical analysis reveals that OPCE yields better HDIC performances on the selected data sets in comparison with eight other HDIC *** demonstrates that OPCE is a viable algorithm to deal with HDIC problems.

关键词： classifier ensemble feature transformation high-dimensional data classification imbalanced learning observation point mechanism

Numerical analysis of landslide-generated debris flow on July 3, 2021 in Izu Mountain area, Shizuoka County, Japan

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Journal of Mountain Science 2022年第6期19卷 1738-1747页

作者： SUN Tong SUN Dong-ya WANG Xie-kang MA Qiang GOURBESVILLE philippe NOHARA Daisuke State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China China Institute of Water Resources and Hydropower Research Beijing 100038China Universite Cote d'Azur Nice 06903France Sustainable Society Laboratory KAJIMA Technical Research Institute Kyoto University 6110011Japan

With the increasing of extreme rainfall frequency, landslides accompanied by mudslides often lead to serious casualties and property damage. On 3rd July 2021, a debris flow occurred in Izu Mountain area, Shizuoka County, Japan, and then resulted in 26 deaths and 131 houses destroyed, where houses were mainly built along the banks of the creek. In order to analyse the landslide state and distribution, a two-dimensional debris flow dynamic model(Massflow) was selected to simulate the process of the landslide-generated debris flow. When the model results are considered together with remote sensing images, the volume distribution of the unstable landslide is also able to be determined. The results show that(1) the affected areas are mainly concentrated at the outfall of the gully and on both sides of the streets.(2) The pore pressure ratio is an important factor affecting the damage range of this debris flow.(3) The increase of the pore pressure ratio in the landslide make the movement distance of debris flow increase significantly.

关键词： Izu Mountain Landslide Debris flow Numerical simulation Pore pressure ratio

A Machine Learning Approach: Enhancing the Predictive Performance of Pharmaceutical Stock Price Movement during COVID

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Journal of Data Analysis and Information Processing 2022年第1期10卷 1-21页

作者： Beilei He Weiyi Han Suet Ying Isabelle hon Jacobs School of Engineering University of California San Diego San Diego USA Xiaohongshu Inc. Shanghai China Centre of Industrial Relations and Human Resources University of Toronto (St. George) Toronto Canada

Predicting stock price movement direction is a challenging problem influenced by different factors and capricious events. The conventional stock price prediction machine learning models heavily rely on the internal financial features, especially the stock price history. However, there are many outside-of-company features that deeply interact with the companies’ stock price performance, especially during the COVID period. In this study, we selected 9 COVID vaccine companies and collected their relevant features over the past 20 months. We added handcrafted external information, including COVID-related statistics and company-specific vaccine progress information. We implemented, evaluated, and compared several machine learning models, including Multilayer Perceptron Neural Networks with logistic regression and decision trees with boosting and bagging algorithms. The results suggest that the application of feature engineering and data mining techniques can effectively enhance the performance of models predicting stock price movement during the COVID period. The results show that COVID-related handcrafted features help to increase the model prediction accuracy by 7.3% and AUROC by 6.5% on average. Further exploration showed that with data selection the decision tree model with gradient, boosting algorithm achieved 70% in AUROC and 66% in the accuracy.

关键词： Machine Learning Stock Price Trend Prediction Feature Engineering

Well-preserved Devonian galeaspid indicates swimming performance of jawless fishes

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National Science Review 2023年第7期10卷 72-72页

作者： philippe Janvier Museum National d’Histoire Naturelle Sorbonne Universtité

A paper by Gai et al.[1] provides the first detailed description of the tail in an exceptionally well-preserved galeaspid from China,and the authors provide some interesting insights into the mode of life and swimming speed in this group of stem *** are a very peculiar group of *** osteostracans,which are currently regarded as a sister group to jawed vertebrates,their gills are enclosed in depressions,or gill fossae,of the ventral surface of the braincase and open ventrally to the exterior by minute *** some galeaspids there may be～50 such gill fossae on each side;that is,the largest number of branchial units ever recorded in vertebrates,along with *** environment and overall aspect of most gale aspids suggest that they were benthic fishes,and that the flux of respiratory water entered the gill apparatus throughthe median dorsal opening (in fact,

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Flat-end tool orientation based on rotation-minimizing frame

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Advances in Manufacturing 2019年第3期7卷 257-269页

作者： Xiang Zou hon-Yuen Tam Hai-Yin Xu Ke Shi School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430074People's Republic of China College of Science and Engineering Department of Mechanical EngineeringCity University of Hong KongHong KongPeople's Republic of China

Well-designed tool orientation is crucial for the quality execution of five-axis machining with flat-end *** orientation can be specified in terms of tool inclination and tool tilt *** a given surface path,these aspects need to be specified for each cutter contact point along the path,because poor tool orientation choice can cause large axial acceleration of the machine tool,leading to inferior quality of the machined *** rotation-minimizing frame aims to reduce unnecessary frame rotation during *** concept has been adopted to develop tool orientation methods that allow variation in the inclination angle,the tilt angle,and both the inclination and tilt *** intention is to reduce unnecessary rotation of the tool frame as the tool follows a specified *** was conducted in the context of five-axis flat-end tool *** on these methods,tool orientation was planned along surface paths of a torus,sphere,and *** in tool orientation were always *** the perspective of reducing tool orientation changes and axial acceleration,it was demonstrated that simultaneous variation of the inclination and tilt angles based on rotation minimization provided the best results.

关键词： Five-axis machining Tool orientation Rotation-minimizing frame Numerical control

Luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline indole complexes as biological probes

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Science China Chemistry 2010年第10期53卷 2091-2098页

作者： LO Kenneth Kam-Wing LEUNG Arthur Ho-hon Department of Biology and Chemistry City University of Hong Kong

Four luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline complexes appended with an indole moiety [Ir(N^C)2(N^N)] (PF6) (HN^C = 2-phenylpyridine, Hppy; N^N = 2-(N-(2-(indole-3-acetamido)ethyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinox- aline, dpqC2indole (1a), N^N = 2-(N-(6-(indole-3-acetamido)hexyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinoxaline, dpqC6indole (1b); HN^C = 7,8-benzoquinoline, Hbzq, N^N = dpqC2indole (2a), N^N = dpqC6indole (2b)) have been synthesized and characterized. Upon irradiation, all the complexes displayed moderately intense and long-lived luminescence under ambient condi-tions and in 77 K glass. On the basis of the photophysical data, the emission of the complexes has been assigned to an excited state of triplet metal-to-ligand charge-transfer (3MLCT) ((dπ(Ir)→π*(N^N)) character. Cyclic voltammetric studies revealed indole-based and iridium-based oxidations at ca. +1.10 V and +1.24 V vs. SCE, respectively, and ligand-based reductions at ca. -1.07 to-2.29 V vs. SCE. The interactions of the complexes with an indole-binding protein, bovine serum albumin (BSA), have been examined by emission titrations.

关键词： binding indole iridium luminescence probes

Pediatric COVID‑19:what disease is this?

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World Journal of Pediatrics 2020年第4期16卷 323-325页

作者： Kam Lun Ellis hon Karen Ka Yan Leung Department of Paediatrics and Adolescent Medicine The Hong Kong Children’s HospitalHong Kong SARChina

The coronavirus disease 2019(COVID-19)pandemic spares no nations or cities causing escalating incidence and ***,prime ministers,celebrities and high government officials alike have been affected by the *** peculiar reasons,children and infants have generally been spared in hong Kong,China until recently,when returning students from affected cities with the virus who largely presented with mild *** fact,several countries have reported on pediatric COVID-19.

关键词： mortality officials Royal