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Entity and relation extraction with rule-guided dictionary as domain knowledge

《工程管理前沿(英文)》   页码 610-622 doi: 10.1007/s42524-022-0226-0

摘要: Entity and relation extraction is an indispensable part of domain knowledge graph construction, which can serve relevant knowledge needs in a specific domain, such as providing support for product research, sales, risk control, and domain hotspot analysis. The existing entity and relation extraction methods that depend on pretrained models have shown promising performance on open datasets. However, the performance of these methods degrades when they face domain-specific datasets. Entity extraction models treat characters as basic semantic units while ignoring known character dependency in specific domains. Relation extraction is based on the hypothesis that the relations hidden in sentences are unified, thereby neglecting that relations may be diverse in different entity tuples. To address the problems above, this paper first introduced prior knowledge composed of domain dictionaries to enhance characters’ dependence. Second, domain rules were built to eliminate noise in entity relations and promote potential entity relation extraction. Finally, experiments were designed to verify the effectiveness of our proposed methods. Experimental results on two domains, including laser industry and unmanned ship, showed the superiority of our methods. The F1 value on laser industry entity, unmanned ship entity, laser industry relation, and unmanned ship relation datasets is improved by +1%, +6%, +2%, and +1%, respectively. In addition, the extraction accuracy of entity relation triplet reaches 83% and 76% on laser industry entity pair and unmanned ship entity pair datasets, respectively.

关键词: entity extraction     relation extraction     prior knowledge     domain rule    

三维体目标间拓扑方向关系描述和推理

刘新,李成名,刘文宝

《中国工程科学》 2013年 第15卷 第5期   页码 8-13

摘要:

空间关系描述了地理信息系统(GIS)中实体间的位置、距离、方位、拓扑等的度量。为提高空间关系描述的惟一性和空间关系推理的准确性,将拓扑关系与方向关系集成描述,构建拓扑方向关系的描述表达模型。目标对象与参照物在X、Y、Z 3个坐标轴上投影间的Allen区间关系分别为[R1]、[R2]和[R3],提出利用Allen区间关系对[(R1,R2,R3)]描述三维拓扑方向区域,用定义法研究拓扑方向关系定性推理,通过一些典型例子说明拓扑方向关系推理过程和结果,推理结果用组合推理表表示。

关键词: 空间关系     拓扑关系     方向关系     拓扑方向关系     三维空间    

Macrozoobenthic assemblages in relation to environments of the Yangtze-isolated lakes

Baozhu PAN, Haijun WANG, Hongzhu WANG, Zhaoyin WANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 246-254 doi: 10.1007/s11783-011-0381-8

摘要: Eutrophication can shift lakes from a clear, macrophyte-dominated state to a turbid, algae-dominated state, and different habitat condition supports different fauna. Macrozoobenthos are good indicators of water environment, and studies on macrozoobenthic assemblage characteristics can help us to know which state a lake is in, thus provide the basis for its eutrophication control. In this study, a systematic investigation on macrozoobenthos was conducted in 17 Yangtze-isolated lakes to explore the macroecological laws of macrozoobenthic assemblages. Detrended correspondence analysis (DCA) revealed that variance of benthic assemblage structure occurred in two types of lakes. In macrophytic lakes, altogether 51?taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2231?individuals·m and 1.69 g dry weight·m , respectively. Macrozoobenthic assemblage was characterized by dominance of scrapers (i.e. gastropods). In algal lakes, altogether 20 taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2814 individuals·m and 1.38 g dry weight·m , respectively. Macrozoobenthic assemblage was characterized by dominance of collector-gatherers (i.e. oligochaetes). Wet biomass of submersed macrophytes ( ) and phytoplankton chlorophyll concentration ( ) were demonstrated as the key factor structuring macrozoobenthic assemblages in macrophytic and algal lakes, respectively.

关键词: macrozoobenthos     assemblage characteristics     environment analyses     macrophytic lake     algal lake    

An extraction- assay system: Evaluation on flavonols in plant resistance to Pb and Cd by supercriticalextraction- gas chromatography

Xu Zhang, Huanhuan Yang, Xinlei Wang, Wen Song, Zhaojie Cui

《环境科学与工程前沿(英文)》 2018年 第12卷 第4期 doi: 10.1007/s11783-018-1059-2

摘要:

SFE-GC system is established for flavonols assessment.

Optimal parameters of SFE-GC are evaluated and determined.

Quercetin and kaempferol are detected in plant under heavy metal stress.

Gene expression analysis shows consistent regularity with content of flavonols.

ROS level is applied for elaborating the plant resistance status.

关键词: Flavonols     Heavy metal     Supercritical carbon dioxide extraction (SFE)     GC     Plant resistance    

Feature extraction from slice data for reverse engineering

ZHANG Yingjie, LU Shangning

《机械工程前沿(英文)》 2007年 第2卷 第1期   页码 25-31 doi: 10.1007/s11465-007-0004-z

摘要: A new approach to feature extraction for slice data points is presented. The reconstruction of objects is performed as follows. First, all contours in each slice are extracted by contour tracing algorithms. Then the data points on the contours are analyzed, and the curve segments of the contours are divided into three categories: straight lines, conic curves and B-spline curves. The curve fitting methods are applied for each curve segment to remove the unwanted points with pre-determined tolerance. Finally, the features, which consist of the object and connection relations among them, are founded by matching the corresponding contours in adjacent slices, and 3D models are reconstructed based on the features. The proposed approach has been implemented in OpenGL, and the feasibility of the proposed method has been verified by several cases.

关键词: feasibility     corresponding     B-spline     pre-determined tolerance     extraction    

A microextraction approach for rapid extraction and separation of Mn(II) and Co(II) using saponified

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 963-972 doi: 10.1007/s11705-021-2081-7

摘要: In this paper, we proposed a microextraction approach for the extraction and separation of Mn(II) and Co(II) from sulfate solution simulating leachate of spent lithium-ion battery cathode materials using saponified di-(2-ethylhexyl)phosphoric acid system. The effects of the following operational variables were investigated: equilibrium pH, tri-n-butyl phosphate concentration, saponification rate, two-phase ratio and residence time. The results showcased that the microextractor can reach the extraction equilibrium within 20 s, thereby greatly reducing necessary extraction time comparing to that of conventional processes. The volumetric mass transfer coefficient showed 8–21 times larger than that of batch device. With the help of microextractor, 95% of Mn(II) was extracted with a single theoretical stage at a chosen two-phase ratio of 3:1, and the separation factor βMn/Co was as large as 65.5. In the subsequent stripping step, more than 99% of manganese from loaded phase was easily stripped under optimal conditions. The microextraction approach greatly enhances the mass transfer while enabling a continuous and controllable extraction process within a simple structure design. When extracting spent electrode material with microextractors, the comprehensive recovery of mangenese can reach 96%. The microextraction approach has a good applicability in the spent lithium-ion battery cathode materials recycling at both bench and industrial scales.

关键词: extraction equilibrium     mass transfer coefficient     microextraction     multicomponent extraction     di-(2-ethylhexyl)phosphoric acid    

A multi-sensor relation model for recognizing and localizing faults of machines based on network analysis

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0736-9

摘要: Recently, advanced sensing techniques ensure a large number of multivariate sensing data for intelligent fault diagnosis of machines. Given the advantage of obtaining accurate diagnosis results, multi-sensor fusion has long been studied in the fault diagnosis field. However, existing studies suffer from two weaknesses. First, the relations of multiple sensors are either neglected or calculated only to improve the diagnostic accuracy of fault types. Second, the localization for multi-source faults is seldom investigated, although locating the anomaly variable over multivariate sensing data for certain types of faults is desirable. This article attempts to overcome the above weaknesses by proposing a global method to recognize fault types and localize fault sources with the help of multi-sensor relations (MSRs). First, an MSR model is developed to learn MSRs automatically and further obtain fault recognition results. Second, centrality measures are employed to analyze the MSR graphs learned by the MSR model, and fault sources are therefore determined. The proposed method is demonstrated by experiments on an induction motor and a centrifugal pump. Results show the proposed method’s validity in diagnosing fault types and sources.

关键词: fault recognition     fault localization     multi-sensor relations     network analysis     graph neural network    

Performance evaluation of an improved biomass-fired cogeneration system simultaneously using extraction

《能源前沿(英文)》 2022年 第16卷 第2期   页码 321-335 doi: 10.1007/s11708-021-0741-4

摘要: An advanced cogeneration system based on biomass direct combustion was developed and its feasibility was demonstrated. In place of the traditional single heat source (extraction steam), the extraction steam from the turbine, the cooling water from the plant condenser, and the low-pressure feedwater from the feedwater preheating system were collectively used for producing district heat in the new scheme. Hence, a remarkable energy-saving effect could be achieved, improving the overall efficiency of the cogeneration system. The thermodynamic and economic performance of the novel system was examined when taking a 35 MW biomass-fired cogeneration unit for case study. Once the biomass feed rate and net thermal production remain constant, an increment of 1.36 MW can be expected in the net electric production, because of the recommended upgrading. Consequently, the total system efficiency and effective electrical efficiency augmented by 1.23 and 1.50 percentage points. The inherent mechanism of performance enhancement was investigated from the energy and exergy aspects. The economic study indicates that the dynamic payback period of the retrofitting project is merely 1.20 years, with a net present value of 5796.0 k$. In conclusion, the proposed concept is validated to be advantageous and profitable.

关键词: biomass-fired cogeneration     district heat production system     absorption heat pump     extraction steam     cooling water     low-pressure feedwater    

Soy food consumption in relation to breast cancer modified by menopause status

YANG Rong, ZHANG Bin, YANG Shaoping, ZHANG Dan, DU Yukai

《医学前沿(英文)》 2008年 第2卷 第4期   页码 348-351 doi: 10.1007/s11684-008-0066-2

摘要: It has been found that lifestyle and diet are associated with the development of cancers. The mortality of breast cancer in Wuhan city is increasing, according to the statistics of recent years. This case control study was aimed to provide data for alimentary therapeutics for breast carcinomas. It included a case group ( = 196) and an age frequency-matched control group ( = 202). A validated food frequency questionnaire was used to obtain information on usual food consumption. The results indicate that intake of soy foods more than 5 times per week was associated with a decreased risk of breast cancer, especially in premenopausal women. The adjusted was 0.294 [95% CI was (0.158–0.546), = 0.000]. Our results indicate that alimentary therapeutics for breast cancer can be adjusted by status of menopause.

关键词: development     control     lifestyle     consumption     information    

Understanding barriers to BIM implementation: Their impact across organizational levels in relation to

Sander SIEBELINK, Hans VOORDIJK, Maaike ENDEDIJK, Arjen ADRIAANSE

《工程管理前沿(英文)》 2021年 第8卷 第2期   页码 236-257 doi: 10.1007/s42524-019-0088-2

摘要: This multiple case study of a contracting firm contributes to understanding the barriers that organizations face during the implementation of building information modeling (BIM) by providing insights into the impact of these barriers across different organizational levels (i.e., from top management to project teams) and by relating these barriers to different degrees of BIM maturity. First, we observe the dominance of barriers related to the motivation, competence, and time capacity of people across all levels of an organization. Second, the cluster of barriers at the middle-management level highlights the important role of this level in reducing these barriers. Third, only those cases with a low level of BIM maturity have struggled with lack of top management support, thereby highlighting the importance of such support in achieving BIM maturity growth. High BIM maturity situations are more prone to externally oriented barriers in attempting to further leverage the benefits of BIM. Our study provides insights on where to focus BIM implementation measures and how to enhance organizational BIM maturity.

关键词: building information modeling     implementation barriers     maturity     organizational levels    

Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

《结构与土木工程前沿(英文)》 2012年 第6卷 第3期   页码 281-287 doi: 10.1007/s11709-012-0167-5

摘要: A new artificial boundary condition for time domain analysis of a structure-unlimited-foundation system was proposed. The boundary condition was based on the damping-solvent extraction method. The principle of the damping-solvent extraction method was described. An artificial boundary condition was then established by setting two spring-damper systems and one artificial damping limited region. A test example was developed to verify that the proposed boundary condition and model had high precision. Compared with the damping-solvent extraction method, this boundary condition is easier to be applied to finite element method (FEM)-based numerical calculations.

关键词: damping-solvent extraction method     structure-unlimited-foundation system     spring-damper system     artificial damping limited region     finite element method    

Study on the microwave-assisted extraction of polyphenols from tea

Liyun WANG, Peiyong QIN, Yan HU,

《化学科学与工程前沿(英文)》 2010年 第4卷 第3期   页码 307-313 doi: 10.1007/s11705-009-0282-6

摘要: This study demonstrated a promising method for quickly extracting tea polyphenol (TP) by microwave-assisted extraction (MAE) technology. Some influential parameters, including MAE temperature, microwave power, concentration of extraction solvent, MAE time and the solid/liquid ratio, were investigated. The optimum condition of MAE was obtained by dual extraction with 60% ethanol (v/v) and the solid/liquid ratio 1:12 g/mL at 80°C for 10 minutes under the microwave power 600 W. The yield of TP was 96.5% under the described condition. Compared with traditional methods, including hot reflux extraction (HRE), ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), the extraction time was saved 8 times than that of HRE, and the yield was increased by 17.5%. The extraction time at comparable levels of production was saved 2 times, and the energy consumption was one fourth that of UAE. The extraction time was saved 5 times than that of SFE, and the yield of TP was increased by 40%. Moreover, compared with MAE of TP studied by others, it decreased the solid/liquid ratio from 1 ∶ 20 to 1 ∶ 12 g/mL without 90-min pre-leaching time, and the yield of TP was increased by 6%–40%.

关键词: energy consumption     microwave-assisted extraction     optimum condition     pre-leaching     concentration    

Oxidation-extraction desulfurization of model oil over Zr-ZSM-5/SBA-15 and kinetic study

Chuanzhu LU,Hui FU,Huipeng LI,Hua ZHAO,Tianfeng CAI

《化学科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 203-211 doi: 10.1007/s11705-014-1420-3

摘要: ZSM-5/SBA-15 composite molecular sieves were synthesized using post-synthesis method and characterized by X-ray diffraction and N adsorption-desorption. The oxidative-extration desulfurization of model oil was investigated by using hydrogen peroxide as the oxidant, tetrabutyl ammonium bromide as phase transfer catalyst, dimethyl sulfoxide as extractant, and Zr-ZSM-5/SBA-15, Ag-ZSM-5/SBA-15, Ce-ZSM-5/SBA-15 as catalyst. Under the optimal conditions, the desulfurization rate decreases in the order: Zr-ZSM-5/SBA-15>Ce-ZSM-5/SBA-15>Ag-ZSM-5/SBA-15. The highest desulfurization rate is 84.53% under the catalysis of Zr-ZSM-5/SBA-15. Kinetics analysis shows that the reaction is pseudo-first-order with the activation energy of 44.23 kJ/mol.

关键词: composite molecular sieve     oxidation desulfuration     extraction     kinetic    

The ITZ microstructure, thickness, porosity and its relation with compressive and flexural strength of

《结构与土木工程前沿(英文)》 2022年 第16卷 第2期   页码 191-201 doi: 10.1007/s11709-021-0792-y

摘要: A new insight into the interfacial transition zone (ITZ) in cement mortar specimens (CMSs) that is influenced by cement fineness is reported. The importance of cement fineness in ITZ characterizations such as morphology and thickness is elucidated by backscattered electron images and by consequences to the compressive (Fc) and flexural strength (Ff), and porosity at various water/cement ratios. The findings indicate that by increasing the cement fineness the calcium silicate hydrate formation in the ITZ is favored and that this can refine the pore structures and create a denser and more homogeneous microstructure. By increasing cement fineness by about 25% of, the ITZ thickness of CMSs was reduced by about 30% and Fc was increased by 7%–52% and Ff by 19%–40%. These findings illustrate that the influence of ITZ features on the mechanical strength of CMSs is mostly related to the cement fineness and ITZ microstructure.

关键词: cement fineness     interfacial transition zone     compressive and flexural strength    

Extraction of hydrogen chloride by a coupled reaction-solvent extraction process

Yunzhao Li,Xingfu Song,Guilan Chen,Shuying Sun,Yanxia Xu,Jianguo Yu

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 479-487 doi: 10.1007/s11705-015-1512-8

摘要: A coupled reaction-solvent extraction process was used to remove HCl from a simulated distiller waste. The extraction performances of various extractants and diluents were compared and the apparent basicity of N235 (a mixture of tertiary amines) in various diluents was determined. The best results were obtained using N235 and isoamyl alcohol as the extractant and diluent, respectively. The yield of HCl from the coupled extraction was 75% with this extraction system. The mechanisms for the removal of HCl in both the direct and coupled extractions were investigated. For the coupled extraction, the formation of an R NHCl ion-pair complex was involved in the HCl removal. For the direct extraction, the mechanism involved the formation of hydrogen bonds at high concentrations of HCl.

关键词: hydrogen chloride     distiller waste     coupled reaction and solvent extraction     N235     extraction mechanism    

标题 作者 时间 类型 操作

Entity and relation extraction with rule-guided dictionary as domain knowledge

期刊论文

三维体目标间拓扑方向关系描述和推理

刘新,李成名,刘文宝

期刊论文

Macrozoobenthic assemblages in relation to environments of the Yangtze-isolated lakes

Baozhu PAN, Haijun WANG, Hongzhu WANG, Zhaoyin WANG

期刊论文

An extraction- assay system: Evaluation on flavonols in plant resistance to Pb and Cd by supercriticalextraction- gas chromatography

Xu Zhang, Huanhuan Yang, Xinlei Wang, Wen Song, Zhaojie Cui

期刊论文

Feature extraction from slice data for reverse engineering

ZHANG Yingjie, LU Shangning

期刊论文

A microextraction approach for rapid extraction and separation of Mn(II) and Co(II) using saponified

期刊论文

A multi-sensor relation model for recognizing and localizing faults of machines based on network analysis

期刊论文

Performance evaluation of an improved biomass-fired cogeneration system simultaneously using extraction

期刊论文

Soy food consumption in relation to breast cancer modified by menopause status

YANG Rong, ZHANG Bin, YANG Shaoping, ZHANG Dan, DU Yukai

期刊论文

Understanding barriers to BIM implementation: Their impact across organizational levels in relation to

Sander SIEBELINK, Hans VOORDIJK, Maaike ENDEDIJK, Arjen ADRIAANSE

期刊论文

Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

期刊论文

Study on the microwave-assisted extraction of polyphenols from tea

Liyun WANG, Peiyong QIN, Yan HU,

期刊论文

Oxidation-extraction desulfurization of model oil over Zr-ZSM-5/SBA-15 and kinetic study

Chuanzhu LU,Hui FU,Huipeng LI,Hua ZHAO,Tianfeng CAI

期刊论文

The ITZ microstructure, thickness, porosity and its relation with compressive and flexural strength of

期刊论文

Extraction of hydrogen chloride by a coupled reaction-solvent extraction process

Yunzhao Li,Xingfu Song,Guilan Chen,Shuying Sun,Yanxia Xu,Jianguo Yu

期刊论文