The current method of case-based design (CBD) can be well practiced forconfiguration design in which design experience knowledge is involved. However, since the designcase is confined to a certain application domain, ...The current method of case-based design (CBD) can be well practiced forconfiguration design in which design experience knowledge is involved. However, since the designcase is confined to a certain application domain, it is difficult for CBD to be applied toconceptual design process that develops concepts to meet design specifications. Firstly, a functionfactor description space is erected to provide an exhibition room for all functions of design cases.Next, the approach for identifying the space state of function factor in description space isproposed, including the determination of the similarities between function factors of design case.And then a general object-oriented representation for design case is presented by bringing the classof function and in-out flow into the current case representation. Finally, a living example forelectro-pet design that illustrates the implementation of the method for case-based conceptualdesign based on distributed design case repositories is described.展开更多
Case retrieval(CR) is critically an important part of case-based design. However few studies attempt to research CR for customer-driven design and analyze the eect of other production factors besides similarity comput...Case retrieval(CR) is critically an important part of case-based design. However few studies attempt to research CR for customer-driven design and analyze the eect of other production factors besides similarity computation. This paper proposes a new CR method for customer-driven design,and requirement-weighting analysis. Fuzzy set theory are integrated into CR process to deal with the fuzzy and imprecision customer requirements. So the proposed method is called weighted fuzzy case retrieval(WFCR). Furthermore,similar case evaluation is added into CR process to demonstrate that the best case is selected not only on the basis of satisifaction for the given requriements,but also on the degree of preference over other cases according to multiple evaluation criteria. Meanwhile,WFCR system is developed and applied to power transformer design to validate its scientificity and practicality. Finally,the paper statistically validated the supriority of WFCR by comparing it with traditional fuzzy case retrieval methods(FCRs),and the comparison indicates that WFCR is more accurate than other FCRs.展开更多
Fixture is an important manufacturing activity. A fixture design system based on case-based reasoning (CBR) is proposed in this paper. A new method of case representation on the basis of fixture function is presented,...Fixture is an important manufacturing activity. A fixture design system based on case-based reasoning (CBR) is proposed in this paper. A new method of case representation on the basis of fixture function is presented, where the case representation is constituted of workpiece knowledge, processing feature knowledge, and fixture feature knowledge. Running the prototype system shows that the knowledge representation method, using cases, s a better way to transform and explain the design knowledge.展开更多
On the basis of the comprehensive analysis about the automatic generation of the injection mold parting surface, the parting surface design method which introduces knowledge and case-based reasoning （CBR） into the c...On the basis of the comprehensive analysis about the automatic generation of the injection mold parting surface, the parting surface design method which introduces knowledge and case-based reasoning （CBR） into the computer-aided design is described by combining with the actual characteristic in injection mold design, and the design process of case-based reasoning method is also given. A case library including the information of parting surface is built with the index of main shape features, The automatic design of the mold parting surface is realized combined with the forward-reasoning method and the similarity solution procedure. The rule knowledge library is also founded including the knowledge, principles and experiences for parting surface design. An example is used to show the validity of the method, and the quality and the efficiency of the mold design are improved.展开更多
Background: Binary as well as polytomous logistic models are widely used for estimating odds ratios when the exposure of prime interest assumes unordered multiple levels under matched pairs case-control design. In our...Background: Binary as well as polytomous logistic models are widely used for estimating odds ratios when the exposure of prime interest assumes unordered multiple levels under matched pairs case-control design. In our previous studies, we have shown that the use of a polytomous logistic model for estimating cumulative odds ratios when the outcome (response) variable is ordinal (in addition to being polytomous) under matched pairs case-control design. The cumulative odds ratios were estimated based on separate fitting of the model at each of the cutpoint level as compared to less than equal to that level. In this paper we propose an alternative method of estimating the cumulative odds ratios and reanalyze the Los Angeles Endometrial Cancer data in the context of dose levels of conjugated oestrogen exposure and development of endometrial cancer under the matched pair case-control design. Methods: In the present study, the cumulative logit model is fitted using a single multinomial logit model for the data. For this, the full maximum likelihood estimation procedure is adopted. A test for equality of the cumulative odds ratios across the exposure levels is proposed. Results: The analysis revealed that there is a strong evidence of risk for developing endometrial cancer due to oestrogen exposure above each of the three dose level as compared to less than equal to that level. The estimated values at the three cutpoint levels were found to be 6.17, 3.60 and 5.16 respectively. Conclusions: The odds of developing endometrial cancer are very high for the users of any amount of oestrogen, even if it is the least dose, as compared to the non-users.展开更多
The procedure during complex system plan design of welding position-locating machine is studied in this paper. The main difficulties in designing welding position-locating machine utilizing computer are discussed as w...The procedure during complex system plan design of welding position-locating machine is studied in this paper. The main difficulties in designing welding position-locating machine utilizing computer are discussed as well. A method of case-based intelligent CAD system for welding position-locating machine ( WMICAD) is put forward through wide research on design methodology. Object-oriented programming method is also applied to Ms system. The basic idea and realizing method are described.展开更多
The jacket structure and transition piece comprise the supporting structure of a bottom-fixed offshore wind turbine(OWT)connected to the steel tower,which determines the overall structural dynamic performance of the e...The jacket structure and transition piece comprise the supporting structure of a bottom-fixed offshore wind turbine(OWT)connected to the steel tower,which determines the overall structural dynamic performance of the entire OWT.Ideally,optimal performance can be realized by effectively coordinating two components,notwithstanding their separate design processes.In pursuit of this objective,this paper proposes a concurrent design methodology for the jacket structure and transition piece by exploiting topology optimization(TO).The TO for a three-legged jacket foundation is formulated by minimizing static compliance.In contrast to conventional TO,two separated volume fractions are imposed upon the structural design domain of the jacket structure and transition piece to ensure continuity.A 5 MW(megawatt)OWT supported by a four-legged or three-legged jacket substructure is under investigation.The external loads are derived from various design load cases that are acquired using the commercial software platform DNV Bladed(Det Norske Veritas).Through a comparative analysis of the fundamental frequency and maximum nodal deformation,it was found that the optimized solution demonstrates a reduced weight and superior stiffness.The findings demonstrate the present concurrent design approach using TO can yield significant benefits by reducing the overall design cycle and enhancing the feasibility of the final design.展开更多
The framework for supporting conceptual design using case-based reasoning is studied. Adesign knowledge representation scheme is presented. It is capable of representing both generalized and specific design knowledge....The framework for supporting conceptual design using case-based reasoning is studied. Adesign knowledge representation scheme is presented. It is capable of representing both generalized and specific design knowledge. A two-phase case retrieval strategy, called index elaboration, is described which supports both requirement-function transformation and function-feature transformation at conceptual design stage. We propose a prototype system and discuss in detail the realization of supporting conceptual design by CBR.展开更多
The paper studies on case-based reasoning of uncertain product attributes in configuration design of a product family. Interval numbers characterize uncertain product attributes. By interpolating a number of certain v...The paper studies on case-based reasoning of uncertain product attributes in configuration design of a product family. Interval numbers characterize uncertain product attributes. By interpolating a number of certain values randomly to replace interval numbers and making projection pursuit analysis on source cases and target cases of expanded numbers, we can get a projection value in the optimal projection direction. Based on projection value, we can construct a case retrieval model of projection pursuit that can handle coexisting certain and uncertain product attributes. The application examples of chainsaw configuration design show that case retrieval is highly sensitive to reliable results.展开更多
This paper describes the design and implementation of a hydraulic circuit design system using case-based reasoning (CBR) paradigm from AI community The domain of hydraulic circuit design and case-based reasoning are ...This paper describes the design and implementation of a hydraulic circuit design system using case-based reasoning (CBR) paradigm from AI community The domain of hydraulic circuit design and case-based reasoning are briefly reviewed Then a proposed methodology in compuer-aided circuit design and dynamic leaning with the use of CBR is described Finally an application example is selected to illustrate the ussfulness of applying CBR in hydraulic circuit design with leaming.展开更多
The traditional teaching methods of one-way cultivation of students can no longer meet the requirements of talent cultivation at this stage.The issue of how to promote students from passive acceptance to the independe...The traditional teaching methods of one-way cultivation of students can no longer meet the requirements of talent cultivation at this stage.The issue of how to promote students from passive acceptance to the independent cognitive understanding stage(i.e.deep learning)has become the focus of geography teaching.Therefore,under the guidance of deep learning theory,this paper takes the“landforms”knowledge unit of the Humanistic Education Edition as an example,improves the classroom teaching means through the unit teaching mode,reconstructs the“landforms”teaching unit,and explores the specific teaching of high school geography unit based on deep learning.This study provides a good example and guidelines for high school geography teaching and learning.展开更多
There has been lack of work efforts on how to optimize cementing and completing parameters in order to prevent casing failure induced by formation slippage in pertroleum industry scope.Once the weak plane fails,the fo...There has been lack of work efforts on how to optimize cementing and completing parameters in order to prevent casing failure induced by formation slippage in pertroleum industry scope.Once the weak plane fails,the formation will become easily undertaken slippage across a large area along its interface.The plenty of horizontal planes of weakness in reservoir formations,as reported for a number of oilfields,can easily undertaken slippage once it fails.To address the problem,three-dimensional finite element models were established by taking into considerations the elastoplastic mechanical characteristics of both the casing and the near-wellbore rock.Two types of casing impairment scenarios were considered:Casing collapse(that causes tubing stuck in the well)and complete casing shear-off.In this study,the critical slip displacement of casing shear damage under both cemented and un-cemented conditions was calculated,and the critical displacement of casing with various wall thicknesses and steel grades was compared.A new cementing practice for the Daqing oilfield was then proposed by optimizing casing parameters according to API standards,and a new research method was also put forward by proposing new casing materials to effectively mitigate casing failure caused by formation slippage for the future.Modeling results indicate that the stress and deformation associated with casing in the un-cemented condition is more diffused and the critical slippage displacement is larger than that in the cemented condition.Therefore,the un-cemented condition is more effective in preventing casing shear failure and easier for casing repair,for the case of casing damage caused by formation shear slippage.Casing elongation is the key parameter of casing shear failure in the un-cemented condition.Lower grade casing exhibits a larger critical slippage displacement because of its higher elongation capacity under stress.Casing with lower grade and smaller thickness provides more advantages in preventing casing damage in formations abundant with horizontal weak layers.If the elongation of casing can be largely improved,the critical displacement value can be increased by 21.40%.Higher grade and thicker casing is adapted for mitigate casing failure caused by formation slippage.展开更多
基金This project is support by National Natural Science Foundation of China(No.59990470)National High Technology Research and Development Program of China (No.2001AA415330).
文摘The current method of case-based design (CBD) can be well practiced forconfiguration design in which design experience knowledge is involved. However, since the designcase is confined to a certain application domain, it is difficult for CBD to be applied toconceptual design process that develops concepts to meet design specifications. Firstly, a functionfactor description space is erected to provide an exhibition room for all functions of design cases.Next, the approach for identifying the space state of function factor in description space isproposed, including the determination of the similarities between function factors of design case.And then a general object-oriented representation for design case is presented by bringing the classof function and in-out flow into the current case representation. Finally, a living example forelectro-pet design that illustrates the implementation of the method for case-based conceptualdesign based on distributed design case repositories is described.
基金the National Natural Science Foundation of China (Nos. 50775140, 50575142 and 60304015)the National High Technology Research and Development Program (863) of China (No. 2008AA04Z113)+1 种基金the National Basic Research Program (973) of China (No. 2006CB705400)the Shanghai Committee of Science and Technology (No. 08JC1412000)
文摘Case retrieval(CR) is critically an important part of case-based design. However few studies attempt to research CR for customer-driven design and analyze the eect of other production factors besides similarity computation. This paper proposes a new CR method for customer-driven design,and requirement-weighting analysis. Fuzzy set theory are integrated into CR process to deal with the fuzzy and imprecision customer requirements. So the proposed method is called weighted fuzzy case retrieval(WFCR). Furthermore,similar case evaluation is added into CR process to demonstrate that the best case is selected not only on the basis of satisifaction for the given requriements,but also on the degree of preference over other cases according to multiple evaluation criteria. Meanwhile,WFCR system is developed and applied to power transformer design to validate its scientificity and practicality. Finally,the paper statistically validated the supriority of WFCR by comparing it with traditional fuzzy case retrieval methods(FCRs),and the comparison indicates that WFCR is more accurate than other FCRs.
文摘Fixture is an important manufacturing activity. A fixture design system based on case-based reasoning (CBR) is proposed in this paper. A new method of case representation on the basis of fixture function is presented, where the case representation is constituted of workpiece knowledge, processing feature knowledge, and fixture feature knowledge. Running the prototype system shows that the knowledge representation method, using cases, s a better way to transform and explain the design knowledge.
文摘On the basis of the comprehensive analysis about the automatic generation of the injection mold parting surface, the parting surface design method which introduces knowledge and case-based reasoning （CBR） into the computer-aided design is described by combining with the actual characteristic in injection mold design, and the design process of case-based reasoning method is also given. A case library including the information of parting surface is built with the index of main shape features, The automatic design of the mold parting surface is realized combined with the forward-reasoning method and the similarity solution procedure. The rule knowledge library is also founded including the knowledge, principles and experiences for parting surface design. An example is used to show the validity of the method, and the quality and the efficiency of the mold design are improved.
文摘Background: Binary as well as polytomous logistic models are widely used for estimating odds ratios when the exposure of prime interest assumes unordered multiple levels under matched pairs case-control design. In our previous studies, we have shown that the use of a polytomous logistic model for estimating cumulative odds ratios when the outcome (response) variable is ordinal (in addition to being polytomous) under matched pairs case-control design. The cumulative odds ratios were estimated based on separate fitting of the model at each of the cutpoint level as compared to less than equal to that level. In this paper we propose an alternative method of estimating the cumulative odds ratios and reanalyze the Los Angeles Endometrial Cancer data in the context of dose levels of conjugated oestrogen exposure and development of endometrial cancer under the matched pair case-control design. Methods: In the present study, the cumulative logit model is fitted using a single multinomial logit model for the data. For this, the full maximum likelihood estimation procedure is adopted. A test for equality of the cumulative odds ratios across the exposure levels is proposed. Results: The analysis revealed that there is a strong evidence of risk for developing endometrial cancer due to oestrogen exposure above each of the three dose level as compared to less than equal to that level. The estimated values at the three cutpoint levels were found to be 6.17, 3.60 and 5.16 respectively. Conclusions: The odds of developing endometrial cancer are very high for the users of any amount of oestrogen, even if it is the least dose, as compared to the non-users.
文摘The procedure during complex system plan design of welding position-locating machine is studied in this paper. The main difficulties in designing welding position-locating machine utilizing computer are discussed as well. A method of case-based intelligent CAD system for welding position-locating machine ( WMICAD) is put forward through wide research on design methodology. Object-oriented programming method is also applied to Ms system. The basic idea and realizing method are described.
基金supports were received from the National Key Research and Development Program of China(2024YFE0208600)New Energy Joint Laboratory of China Southern Power Grid Corporation(GDXNY2024KF03)+2 种基金the National Natural Science Foundation of China(Grant No.U24B2090)National Key R&D Program(No.2022YFB4201300)Science and Technology Project of Huaneng Group(HNKJ24-H78).
文摘The jacket structure and transition piece comprise the supporting structure of a bottom-fixed offshore wind turbine(OWT)connected to the steel tower,which determines the overall structural dynamic performance of the entire OWT.Ideally,optimal performance can be realized by effectively coordinating two components,notwithstanding their separate design processes.In pursuit of this objective,this paper proposes a concurrent design methodology for the jacket structure and transition piece by exploiting topology optimization(TO).The TO for a three-legged jacket foundation is formulated by minimizing static compliance.In contrast to conventional TO,two separated volume fractions are imposed upon the structural design domain of the jacket structure and transition piece to ensure continuity.A 5 MW(megawatt)OWT supported by a four-legged or three-legged jacket substructure is under investigation.The external loads are derived from various design load cases that are acquired using the commercial software platform DNV Bladed(Det Norske Veritas).Through a comparative analysis of the fundamental frequency and maximum nodal deformation,it was found that the optimized solution demonstrates a reduced weight and superior stiffness.The findings demonstrate the present concurrent design approach using TO can yield significant benefits by reducing the overall design cycle and enhancing the feasibility of the final design.
文摘The framework for supporting conceptual design using case-based reasoning is studied. Adesign knowledge representation scheme is presented. It is capable of representing both generalized and specific design knowledge. A two-phase case retrieval strategy, called index elaboration, is described which supports both requirement-function transformation and function-feature transformation at conceptual design stage. We propose a prototype system and discuss in detail the realization of supporting conceptual design by CBR.
文摘The paper studies on case-based reasoning of uncertain product attributes in configuration design of a product family. Interval numbers characterize uncertain product attributes. By interpolating a number of certain values randomly to replace interval numbers and making projection pursuit analysis on source cases and target cases of expanded numbers, we can get a projection value in the optimal projection direction. Based on projection value, we can construct a case retrieval model of projection pursuit that can handle coexisting certain and uncertain product attributes. The application examples of chainsaw configuration design show that case retrieval is highly sensitive to reliable results.
文摘This paper describes the design and implementation of a hydraulic circuit design system using case-based reasoning (CBR) paradigm from AI community The domain of hydraulic circuit design and case-based reasoning are briefly reviewed Then a proposed methodology in compuer-aided circuit design and dynamic leaning with the use of CBR is described Finally an application example is selected to illustrate the ussfulness of applying CBR in hydraulic circuit design with leaming.
文摘The traditional teaching methods of one-way cultivation of students can no longer meet the requirements of talent cultivation at this stage.The issue of how to promote students from passive acceptance to the independent cognitive understanding stage(i.e.deep learning)has become the focus of geography teaching.Therefore,under the guidance of deep learning theory,this paper takes the“landforms”knowledge unit of the Humanistic Education Edition as an example,improves the classroom teaching means through the unit teaching mode,reconstructs the“landforms”teaching unit,and explores the specific teaching of high school geography unit based on deep learning.This study provides a good example and guidelines for high school geography teaching and learning.
基金This work was financially supported by the Science Foundation Project in Heilongjiang Province of China(No.QC2018047).
文摘There has been lack of work efforts on how to optimize cementing and completing parameters in order to prevent casing failure induced by formation slippage in pertroleum industry scope.Once the weak plane fails,the formation will become easily undertaken slippage across a large area along its interface.The plenty of horizontal planes of weakness in reservoir formations,as reported for a number of oilfields,can easily undertaken slippage once it fails.To address the problem,three-dimensional finite element models were established by taking into considerations the elastoplastic mechanical characteristics of both the casing and the near-wellbore rock.Two types of casing impairment scenarios were considered:Casing collapse(that causes tubing stuck in the well)and complete casing shear-off.In this study,the critical slip displacement of casing shear damage under both cemented and un-cemented conditions was calculated,and the critical displacement of casing with various wall thicknesses and steel grades was compared.A new cementing practice for the Daqing oilfield was then proposed by optimizing casing parameters according to API standards,and a new research method was also put forward by proposing new casing materials to effectively mitigate casing failure caused by formation slippage for the future.Modeling results indicate that the stress and deformation associated with casing in the un-cemented condition is more diffused and the critical slippage displacement is larger than that in the cemented condition.Therefore,the un-cemented condition is more effective in preventing casing shear failure and easier for casing repair,for the case of casing damage caused by formation shear slippage.Casing elongation is the key parameter of casing shear failure in the un-cemented condition.Lower grade casing exhibits a larger critical slippage displacement because of its higher elongation capacity under stress.Casing with lower grade and smaller thickness provides more advantages in preventing casing damage in formations abundant with horizontal weak layers.If the elongation of casing can be largely improved,the critical displacement value can be increased by 21.40%.Higher grade and thicker casing is adapted for mitigate casing failure caused by formation slippage.
