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Illuminating Recommendation by Understanding the Explicit Item Relations

Journal of Computer Science & Technology 2018年第4期33卷 739-755页

作者： qi Liu Hong-Ke Zhao Le Wu zhi Li En-Hong chen Anhui Province Key Laboratory of Big Data Analysis and Application University of Science and Technology of China Hefei 230027 China School of Computer and Information Hefei University of Technology Hefei 230009 China School of Software Engineering University of Science and Technology of China Hefei 230051 China

Recent years have witnessed the prevalence of recommender systems in various fields, which provide a personalized recommendation list for each user based on various kinds of information. For quite a long time, most researchers have been pursing recommendation performances with predefined metrics, e.g., accuracy. However, in real-world applications, users select items from a huge item list by considering their internal personalized demand and external constraints. Thus, we argue that explicitly modeling the complex relations among items under domain-specific applications is an indispensable part for enhancing the recommendations. Actually, in this area, researchers have done some work to understand the item relations gradually from ＂implicit＂ to ＂explicit＂ views when recommending. To this end, in this paper, we conduct a survey of these recent advances on recommender systems from the perspective of the explicit item relation understanding. We organize these relevant studies from three types of item relations, i.e., combination-effect relations, sequence-dependence relations, and external-constraint relations. Specifically, the combination-effect relation and the sequence-dependence relation based work models the intra-group intrinsic relations of items from the user demand perspective, and the external-constraint relation emphasizes the external requirements for items. After that, we also propose our opinions on the open issues along the line of understanding item relations and suggest some future research directions in recommendation area.

关键词： recommender system item relation recommendation interpretability

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Decomposition of ammonium sulfate residue in a high solid/gas ratio suspension state with an industrial-scale reactor system(production line)

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Particuology 2015年第5期13卷 107-113页

作者： qi Li Delong Xu Yanxin chen Yanfei Yao zhi Sun Songxiong Ding College of Materials & Mineral Resources Xi'an University of Architecture and Technology Beijing Triumph International Engineering Co. Ltd. Department of Civil Engineering University of Agder

Ammonium sulfate residue is a particulate solid and is produced during the manufacture of ammonium sulfate fertilizer. The residue used in this study contained a large portion of calcium carbonate, from which active lime （CaO） was recovered via thermal decomposition. We used a purpose-built device to decom- pose the residue in a semi-suspension state. We found that CaO had the highest activity when residue was decomposed at 850-900 ~C. Our experiments indicated that ammonium sulfate residue should be decom- posed in a suspension state to produce active CaO. Based on our laboratory test findings, an industrial-scale production line with a high solid/gas ratio in a suspension state was devised. The optimal operating con- ditions for the decomposition of the ammonium sulfate residue to produce high quality CaO were also *** found that the CaCO3 decomposition rate was high and the CaO product was highly active, averaging 170 s by the citric acid method. Morphology measurements showed that the CaO product had a porous structure and a large specific surface ensuring high activity.

关键词： Ammonium sulfate residue Particulate solids Active Ca OSuspension decomposition High solid/gas ratio

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Extracting 21 cm signal by frequency and angular filtering

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Research in Astronomy and Astrophysics 2018年第9期18卷 101-112页

作者： qi-zhi Huang Feng-Quan Wu Reza Ansari Xuelei chen Key Laboratory of Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Universite Paris-Sud LALUMR 8607F-91898 Orsay CedexFrance&CNRS/IN2P3F-91405 OrsayFrance Center for High Energy Physics Peking UniversityBeijing 100871China

Extracting the neutral hydrogen （HI） signal is a great challenge for cosmological 21 cm experiments; both the astrophysical foregrounds and receiver noise are typically several orders of magnitude greater than the 21 cm signal. However, the different properties of the 21 cm signal, foreground and noise can be exploited to separate these components. The foregrounds are generally smooth or correlated over the frequency space along a line of sight （LOS）, while both the 21 cm signal and noise vary stochastically along the same LoS. The foreground can be removed by filtering out the smooth component in frequency space. The receiver noise is basically uncorrelated for observations at different times, hence for surveys it is also uncorrelated in different directions, while the 21 cm signal, which traces the large scale structure, is correlated up to certain scales. In this exercise, we apply Wiener filters in frequency and angular space to extract the 21 cm signals. We found that the method works well. Inaccurate knowl- edge about the beam could degrade the reconstruction, but the overall result is still good, showing that the method is fairly robust.

关键词： methods: data analysis - (cosmology:) dark ages reionization first stars - cosmology:observations

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Impacts of Dirty Data on Classification and Clustering Models:An Experimental Evaluation

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Journal of Computer Science & Technology 2021年第4期36卷 806-821页

作者： zhi-Xin qi Hong-zhi Wang An-Jie Wang School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China

Data quality issues have attracted widespread attentions due to the negative impacts of dirty data on data mining and machine learning *** relationship between data quality and the accuracy of results could be applied on the selection of the appropriate model with the consideration of data quality and the determination of the data share to ***,rare research has focused on exploring such *** by this,this paper conducts an experimental comparison for the effects of missing,inconsistent,and conflicting data on classification and clustering *** the experimental results,we observe that dirty-data impacts are related to the error type,the error rate,and the data *** on the findings,we suggest users leverage our proposed metrics,sensibility and data quality inflection point,for model selection and data cleaning.

关键词： data quality classification clustering model selection data cleaning

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Xiangbinfang granules enhance gastric antrum motility via intramuscular interstitial cells of Cajal in mice

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World Journal of Gastroenterology 2021年第7期27卷 576-591页

作者： qi-cheng chen zhi Jiang Jun-Hong Zhang Li-Xing Cao zhi-qiang chen The Research Team of TCM Applications of Perioperative The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong Provincial Hospital of Traditional Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Department of Research Public Service Center The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong Provincial Hospital of Traditional Chinese MedicineGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Interdigestive migrating motor complexes(MMC)produce periodic contractions in the gastrointestinal tract,but the exact mechanism of action still remains *** interstitial cells of Cajal(ICC-IM)participate in gastrointestinal hormone and neuromodulation,but the correlation between ICCIM and MMC is also *** found that xiangbinfang granules(XBF)mediated the phase III contraction of ***,the effects of XBF on gastric antrum motility in W/Wv mice and the effects of ICC-IM on gastric antrum MMC are *** To observe the effects of ICC-IM on gastric antrum motility and to establish the mechanism of XBF in promoting gastric antrum *** The density of c-kit-positive ICC myenteric plexus(ICC-MP)and ICC-IM in the antral muscularis of W/Wv and wild-type(WT)mice was examined by confocal *** effects of XBF on gastric antrum slow waves in W/Wv and WT mice were recorded by intracellular amplification ***-strain-gauge force transducers were implanted into the gastric antrum to monitor the MMC and the effect of XBF on gastric antrum motility in conscious W/Wv and WT *** In the gastric antrum of W/Wv mice,c-kit immunoreactivity was significantly reduced,and no ICC-IM network was *** rhythmic slow waves also appeared in the antrum of W/Wv mice,but the amplitude of the antrum slow wave decreased significantly in W/Wv mice(22.62±2.23 mV vs 2.92±0.52 mV,P<0.0001).MMCs were found in 7 of the 8 WT mice but no complete MMC cycle was found in W/Wv *** contractile frequency and amplitude index of the gastric antrum were significantly increased in conscious WT compared to W/Wv mice(frequency,3.53±0.18 cpm vs 1.28±0.12 cpm;amplitude index,23014.26±1798.65 mV·20 min vs 3782.16±407.13 mV·20 min;P<0.0001).XBF depolarized smooth muscle cells of the gastric antrum in WT and W/Wv mice in a dose-dependent ***,the gastric antrum motility in WT mice was significantly increased after

关键词： Interstitial cells of Cajal Migrating motor complex W/Wv Gastric antrum motility Xiangbinfang granules Chinese medicine

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Characterization of the microbial community response to replant diseases in peach orchards

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Journal of Integrative Agriculture 2023年第4期22卷 1082-1092页

作者： LI Wei-hua chen Peng WANG Yu-zhu LIU qi-zhi Laboratory of Entomology and Nematology College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101P.R.China Key Laboratory of Natural Enemies Insects of Ministry of Agriculture and Rural Affairs Shandong Provincial Engineering Technology Research Center on Biocontrol of Crop Diseases and Insect PestInstitute of Plant ProtectionShandong Academy of Agricultural SciencesJinan 250100P.R.China Institute of Forestry and Pomology Beijing Academy of Agriculture and Forestry SciencesBeijing 100093P.R.China

This study attempted to monitor the development of microbial communities and reveal the correlation between the soil microbial community and soil nutrient factors over different years following the replanting of peach *** replanted soil(RS)and nonreplanted soil(NRS)were collected from peach orchards with different growth years(1,3,5,7,9,11,and 13 years)in the same *** soil bacterial and fungal community diversities were analyzed by high-throughput sequencing *** analysis(RDA)was used to show the correlation between the soil microbial community and environmental *** alpha diversities of the bacterial and fungal communities indicated that RS contained a higher abundance of bacterial and fungal operational taxonomic units(OTUs)than *** and ANOSIM analyses showed that the soil bacterial and fungal communities were significantly(P3.0).In addition,the soil nutrient contents were lower in RS than in NRS in the early stage(1–5 years),and the RDA showed that bacterial and fungal phyla are closely associated with environmental variables,including the potential of hydrogen(pH),ammonium nitrogen(AN),available phosphorus(AP)and available potassium(AK).These results lead to a deeper understanding of the microbial responses to replanting in peach orchards.

关键词： replant disease complex syndrome microbial community high-throughput sequencing environmental variables

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A review of behavior mechanisms and crowd evacuation animation in emergency exercises

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第7期14卷 477-485页

作者： Gao-qi HE Yu YANG zhi-hua chen Chun-hua GU zhi-geng PAN Department of Computer Science and Engineering East China University of Science and Technology Digital Media and Interaction Research Center Hangzhou Normal University

Emergency exercises are an efficient approach for preventing serious damage and harm, including loss of life and property and a wide range of adverse social effects, during various public emergencies. Among various factors affecting the value of emergency exercises, including their design, development, conduct, evaluation, and improvement planning, this paper emphasizes the focal role of evacuees and their behavior. We address two concerns: What are the intrinsic reasons behind human behavior? How do we model and exhibit human behavior? We review studies investigating the mechanisms of psychological behavior and crowd evacuation animation. A comprehensive analysis of logical patterns of behavior and crowd evacuation is presented first. The interactive effects of information (objective and subjective), psychology (panic, small groups, and conflicting roles), and six kinds of behavior contribute to a more effective understanding of an emergency scene and assist in making scientific decisions. Based on these studies, a wide range of perspectives on crowd formation and evacuation animation models is summa- rized. Collision avoidance is underlined as a special topic. Finally, this paper highlights some of the technical challenges and key questions to be addressed by future developments in this rapidly developing field.

关键词： Emergency exercises Behavior mechanisms Crowd evacuation animation Collision avoidance

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Study on the failure mechanism of Ag-Ce contacts in DC level

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 449-452页

作者： MENG Fan-bin LU Jian-guo LU Ning-yi chen zhi-chao chen qi School of Materials Science and Engineering Hebei Univertity of Technology Tianjin 300130 China Hongfa Electroacoustic Co. Ltd Xiamen 361021 China

Nominal contact resistance, minimum erosion and material transfer are required with low cost materials working in a wide currents range for DC relays. Ag-Ni contact materials have low contact resistance, but the erosion and material transfer are large at high current level. Ag-SnO2 contact materials have good anti-welding properties and resistance to arc erosion, but they have large contact resistance during working and are easily block SnO2 from flocking together on the surface at low current level. In this paper, the failure mechanisms of Ag-Ce contact material were studied. The surface morphologies of the contacts after electrical endurance test for Ag-Ce contact material were compared with that of Ag-Ni and Ag-SnO2 contact materials. The effect of Ce on the surface morphologies of the contacts after electrical endurance test was analyzed.

关键词： Relays Electric contact Failure analysis

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闷黄前日晒处理对黄茶香气的影响

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食品工业科技 2025年第1期46卷 13-21页

作者：陈新颖亓俊然张丽霞山东农业大学园艺科学与工程学院山东泰安271018

为探究在鲜叶低温处理基础上,“日晒”与“闷黄”以及两者相互作用对黄茶香气品质的影响,本文以5℃、18 h低温处理的‘金萱’一芽一叶鲜叶为原料,设置不同时长的闷黄前日晒处理、湿坯闷黄处理以及两者组合处理工艺,对所得茶样通过感官... 详细信息

为探究在鲜叶低温处理基础上,“日晒”与“闷黄”以及两者相互作用对黄茶香气品质的影响,本文以5℃、18 h低温处理的‘金萱’一芽一叶鲜叶为原料,设置不同时长的闷黄前日晒处理、湿坯闷黄处理以及两者组合处理工艺,对所得茶样通过感官审评和顶空固相微萃取-气质联用仪进行分析。结果表明,揉捻叶在光强为1700±50μmol∙m^(-2)∙s^(-1)、室外温度为35±5℃、空气湿度为30%±5%的环境条件下,日晒处理0.5 h,随后在温度45℃、湿度70%的环境下湿坯闷黄3 h获得的黄茶品质最优,与湿坯闷黄3 h的对照茶样相比,其香气物质总量增加91.26%,其中呈甜香和花果香型的酮类、醛类、醇类和酯类物质的含量分别为对照茶样的6.18、5.55、3.79和2.99倍,呈清香型的含硫香气组分含量降低26.72%,提高了‘金萱’黄茶香气浓度,促进其香型的转变。此外,日晒处理和湿坯闷黄处理之间存在相互作用,日晒处理可以有效缩短湿坯闷黄时长,同时湿坯闷黄处理有利于去除日晒处理带来的日腥味,并进一步提升‘金萱’黄茶香气品质。

关键词：黄茶香气日晒处理闷黄

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Regional volume changes of the brain in migraine chronification

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Neural Regeneration Research 2020年第9期15卷 1701-1708页

作者： Xiao-Yan chen zhi-Ye chen Zhao Dong Meng-qi Liu Sheng-Yuan Yu Department of Neurology First Medical Center of Chinese PLA General HospitalBeijingChina Department of Radiology First Medical Center of Chinese PLA General HospitalBeijingChina Department of Radiology Hainan Hospital of First Medical Center of Chinese PLA General HospitalSanyaHainan ProvinceChina

The pathophysiology of migraine is *** studies reveal functional and structural changes in the brains of migraine *** sought to explore regional volume differences in intracranial structures in patients with episodic and chronic *** episodic migraine patients,16 chronic migraine patients,and 24 normal controls were recruited and underwent 3.0 T MRI *** volumes of 142 brain regions were calculated by an automatic volumetric algorithm and compared with clinical *** demonstrated that the volumes of specific regions in the frontal and occipital lobes,and the right putamen,were increased and the volume of the fourth ventricle was decreased in the episodic migraine patients compared with *** volumes of the left basal forebrain,optic chiasm,and,the fourth ventricle were decreased in the chronic migraine patients,while the occipital cortex and the right putamen were *** to episodic migraine patiants,chronic migraine patients displayed larger left thalamus and smaller frontal *** analysis showed that headache frequency was negatively correlated with the volume of the right frontal pole,right lateral orbital gyrus,and medial frontal lobes and positively correlated with the volume of the left *** sleep disturbance score was negatively correlated with the volume of the left basal *** suggests that migraine patients have structural changes in regions associated with pain processing and modulation,affective and cognitive processing,and visual *** remodeling of selective intracranial structures may be involved in migraine *** study was approved by the Ethics Committee of Chinese PLA General Hospital(approval No.S2018-027-02)on May 31,2018.

关键词： brain volume chronic migraine frontal lobe magnetic resonance imaging migraine remodeling thalamus visual processing system

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