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A QUANTIFIER-ELIMINATION BASED HEURISTIC FOR AUTOMATICALLY GENERATING INDUCTIVE ASSERTIONS FOR PROGRAMS 被引量:3
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作者 Deepak KAPUR 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2006年第3期307-330,共24页
A method using quantifier-elimination is proposed for automatically generating program invariants/inductive assertions. Given a program, inductive assertions, hypothesized as parameterized formulas in a theory, are as... A method using quantifier-elimination is proposed for automatically generating program invariants/inductive assertions. Given a program, inductive assertions, hypothesized as parameterized formulas in a theory, are associated with program locations. Parameters in inductive assertions are discovered by generating constraints on parameters by ensuring that an inductive assertion is indeed preserved by all execution paths leading to the associated location of the program. The method can be used to discover loop invariants-properties of variables that remain invariant at the entry of a loop. The parameterized formula can be successively refined by considering execution paths one by one; heuristics can be developed for determining the order in which the paths are considered. Initialization of program variables as well as the precondition and postcondition, if available, can also be used to further refine the hypothesized invariant. The method does not depend on the availability of the precondition and postcondition of a program. Constraints on parameters generated in this way are solved for possible values of parameters. If no solution is possible, this means that an invariant of the hypothesized form is not likely to exist for the loop under the assumptions/approximations made to generate the associated verification condition. Otherwise, if the parametric constraints are solvable, then under certain conditions on methods for generating these constraints, the strongest possible invariant of the hypothesized form can be generated from most general solutions of the parametric constraints. The approach is illustrated using the logical languages of conjunction of polynomial equations as well as Presburger arithmetic for expressing assertions. 展开更多
关键词 Automated software analysis and verification inductive assertion loop invariant quantifier elimination.
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PARAMETRIC EQUATION SOLVING AND QUANTIFIER ELIMINATION IN FINITE FIELDS WITH THE CHARACTERISTIC SET METHOD 被引量:3
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作者 Zhenyu HUANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第4期778-791,共14页
For a parametric algebraic system in finite fields, this paper presents a method for computing the cover and the refined cover based on the characteristic set method. From the cover, the author knows for what parametr... For a parametric algebraic system in finite fields, this paper presents a method for computing the cover and the refined cover based on the characteristic set method. From the cover, the author knows for what parametric values the system has solutions and at the same time presents the solutions in the form of proper chains. By the refined cover, the author gives a complete classification of the number of solutions for this system, that is, the author divides the parameter space into several disjoint components, and on every component the system has a fix number of solutions. Moreover, the author develops a method of quantifier elimination for first order formulas in finite fields. 展开更多
关键词 Characteristic set method finite field parametric equation system quantifier elimination.
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Variant quantifiers in L_(3)-valued first-order logic
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作者 Wei LI Yuefei SUI 《Frontiers of Computer Science》 SCIE EI CSCD 2021年第5期151-159,共9页
Traditional first-order logic has four definitions for quantifiers,which are defined by universal and existential quantifiers.In L_(3)-valued(three-valued)first-order logic,there are eight kinds of definitions for qua... Traditional first-order logic has four definitions for quantifiers,which are defined by universal and existential quantifiers.In L_(3)-valued(three-valued)first-order logic,there are eight kinds of definitions for quantifiers;and corresponding Gentzen deduction systems will be given and their soundness and completeness theorems will be proved. 展开更多
关键词 L_(3)-valued(three-valued)first-order logic sequent quantifier soundness theorem completeness theorem
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中英文化中量词对比研究(英文) 被引量:3
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作者 宋淑敏 《齐齐哈尔大学学报(哲学社会科学版)》 2006年第4期139-140,共2页
Chinese has special quantifiers as a part of speech while English does not have independent quantifiers.To some degree,the difference comes from the different cultural backgrounds.
关键词 CHINESE English quantifier DIFFERENCE CULTURE
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Three methods for generating monotonic OWA operator weights with given orness level 被引量:1
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作者 刘新旺 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期369-373,共5页
Based on the properties of ordered weighted averaging (OWA) operator and regular increasing monotone (RIM) quantifier, three methods for generating monotonic OWA operator weights are proposed. They are geometric OWA o... Based on the properties of ordered weighted averaging (OWA) operator and regular increasing monotone (RIM) quantifier, three methods for generating monotonic OWA operator weights are proposed. They are geometric OWA operator weights, equidifferent OWA operator weights and the modified RIM quantifier OWA weights. Compared with most of the common OWA methods for generating weights, the methods proposed in this paper are more intuitive and efficient in computation. And as there are more than one solution in most cases, the decision maker can set some initial condition and chooses the appropriate solution in the real decision process, which increases the flexibility of decision making to some extent. All these three OWA methods for generating weights are illustrated by numerical examples. 展开更多
关键词 ordered weighted averaging operator orness measure fuzzy quantifier
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The Rational Man Model in Social and Political Studies: A Plea for Relevance 被引量:1
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作者 Gerardo M. Acay 《Journal of Literature and Art Studies》 2015年第1期86-92,共7页
This paper examines the assumptions of the Rational Man (RM) model familiar in social and political studies. It is observed that the model is too restrictive in its explaining events and behavior in social and polit... This paper examines the assumptions of the Rational Man (RM) model familiar in social and political studies. It is observed that the model is too restrictive in its explaining events and behavior in social and political situations. It is suggested that the assumptions of RM model should be relaxed using the familiar methods and techniques of elementary formal logic. The concept of relevance is then introduced to take account of a "weaker" formal requirement in an attempt to explain events and processes in human action and/or behavior. The concept of "justification by reasons" is then introduced as a necessary though not sufficient requirement of explaining events and processes in social and political studies 展开更多
关键词 rational MODEL logic quantifierS RELEVANCE JUSTIFICATION
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Heuristics in Language Comprehension
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作者 Veena D. Dwivedi Kaitlin E. Goertz Janahan Selvanayagam 《Journal of Behavioral and Brain Science》 2018年第7期430-446,共17页
We used a sentence-picture matching task to demonstrate that heuristics can influence language comprehension. Interpretation of quantifier scope ambiguous sentences such as Every kid climbed?a tree was investigated. S... We used a sentence-picture matching task to demonstrate that heuristics can influence language comprehension. Interpretation of quantifier scope ambiguous sentences such as Every kid climbed?a tree was investigated. Such sentences are ambiguous with respect to the number of trees inferred;either several trees were climbed or just one. The availability of the NOUN VERB NOUN (N-V-N) heuristic, e.g., KID CLIMB TREE, should contribute to the interpretation of how many trees were climbed. Specifically, we hypothesized that number choices for these stimuli would be predicted by choices previously made to corresponding (full) sentences. 45 participants were instructed to treat N-V-N triplets such as KID CLIMB TREE as telegrams and select a picture, regarding the quantity (“several” vs. “one”) associated with tree. Results confirmed that plural responses to quantifier scope ambiguous sentences significantly predict increased plural judgments in the picture-matching task. This result provides empirical evidence that the N-V-N heuristic, via conceptual event knowledge, can influence sentence interpretation. Furthermore, event knowledge must include the quantity of participants in the event (especially in terms of “several” vs. “one”). These findings are consistent with our model of language comprehension functioning as “Heuristic first, algorithmic second.” Furthermore, results are consistent with judgment and decision making in other cognitive domains. 展开更多
关键词 CONCEPTUAL EVENT Knowledge Language quantifier SCOPE SCRIPTS HEURISTICS
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Sequential Predication
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作者 Eugeniusz Wojciechowski 《Journal of Philosophy Study》 2015年第5期244-256,共13页
Vladimir Markin proposes a certain construction---a generalisation of syllogistic--in which he uses the constant @ with indef'mite arity. The atomic formulae are of the following sort: S1S2 ...Sm@P1P2...Pn, where re... Vladimir Markin proposes a certain construction---a generalisation of syllogistic--in which he uses the constant @ with indef'mite arity. The atomic formulae are of the following sort: S1S2 ...Sm@P1P2...Pn, where re+n〉0. The standard syllogistic functors are here interpreted as follows: SAP=: S@P SeP=: SP@ SIP=: -SP@ SOP=: ~S@P Markin constructs a system of Fundamental Syllogistic (FS) with constant @ in an axiomatic way. Based on Markin's idea, we propose two constructions, which are formulations of the system of sequential predication built upon the quantifier-less calculus of names. The first one includes the FS system. The second one is enriched with individual variables and, among other things, allows including sequences of individual names in which one has to do with enumerative functors. The counterpart of Hao Wang's algorithm holds in the first system extended with negative terms. 展开更多
关键词 sequential predication generalization of syllogistic quantifier.less calculus of names Hao Wang'salgorithm
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Noun Phrase in Mesqan
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作者 Ousman Shafi 《宏观语言学》 2019年第1期97-104,共8页
Mesqan is a South Ethio-Semitic tonguewhich is mainly worn in day-to-day message by a people of on 179,737 communities in the Gurage Zone,Ethiopia,whose linguistic skin were not well expressed.The inner aspire of this... Mesqan is a South Ethio-Semitic tonguewhich is mainly worn in day-to-day message by a people of on 179,737 communities in the Gurage Zone,Ethiopia,whose linguistic skin were not well expressed.The inner aspire of this paper is to offer a complete account of noun phrase structures of the Mesqan tongue.The paper is expressive in character,as the lessons is mostly worried with telling what is really being in the tongue,and mostly relies on main linguistic facts.The linguistic facts,i.e.the elicited grammatical facts regarding noun phrases,was composed from local speakers of the tongue during 12 months of fieldwork mannered among 2011 and 2012 in four Mesqan villages and in Butajira,the managerial hub of the Mesqan Woreda.The head of a NP can be a pronoun,a noun or an adjective.The head alone can constitute a full noun phrase.Adjectives,nouns in the genitive,or relative clauses function as modifiers of head nouns.Quantifiers are numerals,unspecific quantifiers,determiners include the definite marker,demonstrative pronouns,and possessive suffixes occur in two positions to the head noun.Only the demonstrative pronouns and the number‘one’when used as indefinite marker occur in phrase-initial position,while all other determiners follow the head. 展开更多
关键词 quantifierS NUMERALS DETERMINERS demonstrative suffixes GENITIVE PHRASE possessive
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A Cross-Linguistic Comparison of Determiner Arrangement and its Pedagogic Implications
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作者 赵娟 《海外英语》 2012年第16期262-265,共4页
The surface configurations of quantifiers and scope-determiners in Chinese and English NPs show both similarities and differences which may result in acquisition bewilderment for Chinese learners of English. Various E... The surface configurations of quantifiers and scope-determiners in Chinese and English NPs show both similarities and differences which may result in acquisition bewilderment for Chinese learners of English. Various English determiners are found to play unequal cognitive roles in terms of their semantic weight. An explanatory method is suggested to address language-specific cognitive features. It may render L2 acquisition a more insightful process and minimize the L1 interference. 展开更多
关键词 quantifier scope-determiner arrangement SEMANTIC w
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ROLE OF B LYMPHOCYTE AND ITS SUBPOPULATIONS IN PATHOGENESIS OF IMMUNORELATED PANCYTOPENIA 被引量:10
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作者 Rong Fu Zong-hong Shao Hong Liu Yu-hong Wu Hua-quan Wang Li-min Xing 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第3期199-202,共4页
Objective To measure the quantities and apoptosis-related protein levels of B lymphocyte in the patients with immunorelated pancytopenia (IRP) and explore the action of B lymphocyte in the pathogenic mechanism of IR... Objective To measure the quantities and apoptosis-related protein levels of B lymphocyte in the patients with immunorelated pancytopenia (IRP) and explore the action of B lymphocyte in the pathogenic mechanism of IRP. Methods Quantifies of whole B lymphocytes and CD5^+ B lymphocytes as well as the expressions of Fas and Bcl-2 in B lymphocytes in 35 patients with untreated IRP, 15 IRP patients in complete remission (CR), and 10 normal controls were assayed by flow cytometry. The percentages of B lymphocyte and CD5^+ B lymphocyte were significantly higher in untreated IRP patients than in CR IRP patients and normal controls ( P 〈 0. 05 ), and there was no significant difference between the latter two groups ( P 〉 0. 05 ). There was no significant difference of Fas expression in B lymphocyte among three groups ( P 〉 0. 05). The expression of Bcl-2 in B lymphocyte was significantly higher in untreated patients than in CR patients or normal controls ( P 〈 0. 01 ), and significantly higher in CR patients than in normal controls ( P 〈 0. 01 ). The apoptosis. related index was significantly lower in untreated patients than in CR patients or normal controls ( P 〈 0. 05 ), and signif. icantly lower in CR patients than in normal controls ( P 〈 0. 05 ). The percentage of B lymphocyte was positively correlated with post-treated response time ( r = 0. 53, P 〈 0. 01 ). Conclusion The production of auto-antibodies in IRP patients probably has some relationship with the abnormal quantifies of B lymphocyte and its subpopulations as well as with the inhibition of B lymphocyte apoptosis. 展开更多
关键词 immunorelated pancytopenia B lymphocyte quantifies APOPTOSIS
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Reliability analysis of geotechnical infrastructures: Introduction 被引量:3
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作者 Wengang Zhang Anthony Teck Chee Goh 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1595-1596,共2页
In the design of geotechnical infrastructure,engineers have to deal with naturally occurring soils and rocks which are subjected to spatial variability as well as other uncertainties such as errors in measurement and ... In the design of geotechnical infrastructure,engineers have to deal with naturally occurring soils and rocks which are subjected to spatial variability as well as other uncertainties such as errors in measurement and in modeling methods.Reliability assessment which provides a systematic approach for quantifying the risk of failure has been shown to be a promising tool for solving these challenging geotechnical engineering problems.The method provides a more consistent measure of the level of safety or“structural reliability”through the evaluation of a reliability index and the associated“failure”probability,and is a method that satisfies the need to clearly convey safety issues to the public and regulatory authorities.Various methods for calculating the reliability of geotechnical infrastructures with regard to the assessment of the ultimate and serviceability limit states have been proposed by many researchers and these approaches include:the direct Monte Carlo Simulation,Bayesian and other sampling techniques,the first-order reliability method and the second-order reliability method,the random field method,the response surface method and other surrogate models with the related probabilistic procedures.In this special issue of Geoscience Frontiers,we assemble eleven invited papers which provide insights on the latest developments and challenges in applying probabilistic and reliability methods to geotechnical infrastructure design. 展开更多
关键词 GEOTECHNICAL INFRASTRUCTURE quantifying the risk of FAILURE
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Orthogonal design to sift the optimal parameter of Neiguan acupuncture for cerebral infarction 被引量:7
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作者 Yanan Zhang Sha Yang +5 位作者 Xiaonong Fan Shu Wang Nina He Lingxin Li Ding Luo Xuemin Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第28期2641-2648,共8页
The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to cont... The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to control needle depth, lifting and thrusting frequency, and the duration of acupuncture. Effects of the quantified acupuncture were observed at Neiguan (PC6) with different stimulation parameters. A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery. Results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume. In- teractions between frequency and duration play a critical role in quantified acupuncture therapy. 展开更多
关键词 neural regeneration ACUPOINT quantified acupuncture NEIGUAN middle artery occlusion injury lift-ing and thrusting method orthogonal design lifting and thrusting frequency acupuncture duration grants-supported paper NEUROREGENERATION
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Correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma 被引量:8
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作者 Shenjiang Li Xiangsheng Xiao +3 位作者 Shiyuan Liu Huimin Li Chengzhou Li Chenshi Zhang 《The Chinese-German Journal of Clinical Oncology》 CAS 2007年第4期345-349,共5页
Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarci... Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarcinomas (SBA)(diameter≤4 cm)underwent multi-location dynamic contrast material-enhanced(nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/s by using an autoinjector 90 mL,4×5 mm or 4×2.5 mm scanning mode with stable table were performed)serial CT.Precontrast and postcontrast attenuation on every scan was recorded.Perfusion (PBA),peak height(PHBA),ratio of peak height of the SPN to that of the aorta(BA-to-A ratio)and mean transit time(MTT)were calculated.The correlation between peak height of the aorta(PHA)and parameters of the SBA(PHBA,BA-to-A ratio,PBA,and MTT)and those among parameters of the SBA were assessed by means of linear regression analysis.Regression equation among parameters of the SBA were obtain by means of stepwise regression.Results:The correlation between the SBA peak height(PHBA,36.78 HU±12.02)and the aortic peak height(PHA)was significant(r=0.506,P<0.0001).No significant cor- relation was found between the BA-to-Apeak height ratio(15.33%±4.55)and the aortic peak height(r=0.130,P=0.388> 0.05)as it was between the SBA perfusion(PBA,31.86 mL/min/100 g±9.74)and the aortic peak height(r=0.049,P=0.749 >0.05).The SBA perfusion correlated with the PHBA and the BA-to-A peak height ratio(r=0.394,P=0.007<0.05;r=0.407, P=0.005<0.05).The PHBA correlated positively with the BA-to-A peak height ratio(r=0.781,P<0.0001).Mean transit time was 14.84 s±5.52.PBA=18.500+0.872×BA-to-A ratio.BA-to-A ratio=4.467+0.295×PHBA.Conclusion:The linear correlation between the SBA perfusion and BA-to-Aratio and that between BA-to-Aratio and PHBA can be expressed by equation. It is possible to design a simpler scanning procedure of investigation of bronchogenic adenocarcinoma angiogenesis. 展开更多
关键词 bronchogenic adenocarcinoma blood flow pattern CT quantifiable parameters linear correlation
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Correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size 被引量:3
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作者 Shenjiang Li Xiangsheng Xiao +3 位作者 Shiyuan Liu Huimin Li Chengzhou Li Chenshi Zhang 《The Chinese-German Journal of Clinical Oncology》 CAS 2006年第5期324-327,共4页
Objective: To evaluate the correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size. Methods: Sixty-eight patients with mal... Objective: To evaluate the correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size. Methods: Sixty-eight patients with malignant solitary pulmonary nodules (SPNs) (diameter 〈4 cm) underwent multi-location dynamic contrast material-enhanced (nonionic contrast material was administrated via the antecubitai vein at a rate of 4mL/s by using an autoinjector, 4×5 mm or 4×2.5 mm scanning mode with stable table were performed). Precontrast and postcontrast attenuation on every scan was recorded. Blood flow (BF), peak, height (PHSPN), ratio of peak height of the SPN to that of the aorta (SPN-to-A ratio) and mean transit time (MTT) were calculated. The correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size were assessed by means of linear regression analysis. Results: No significant correlations were found between the tumor size and each of the peak height (PHSPN) (35.79±10.76 Hu), ratio of peak height of the SPN to that of the aorta (SPN-to-A ratio), (14.27%±4.37) and blood flow (BF) (30.18 mL/min/100 g±9.58) (r=0.180, P=0.142〉0.05; r=0.205, P=0.093〉0.05; r=0.008, P=0.947〉0.05). Conclusion: No significant correlations were found between the tumor size and each of the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules. 展开更多
关键词 MALIGNANT solitary pulmonary nodules blood flow pattern CT quantifiable parameters
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GERM CELL MUTATIONS IN MICE:STANDARDS FOR PROTECTING THE HUMAN GENOME 被引量:1
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作者 Udo H.Ehling 《癌变.畸变.突变》 CAS CSCD 1991年第S1期35-35,共1页
The most extensive set of information on the factorsaffecting mutation induction by chemical mutagens inmice has been obtained by use of the dominant lethalassay and the specific locus method.Dominant lethalmutations ... The most extensive set of information on the factorsaffecting mutation induction by chemical mutagens inmice has been obtained by use of the dominant lethalassay and the specific locus method.Dominant lethalmutations are caused by chromosomal aberrations,and they occur shortly before or after implantation. 展开更多
关键词 CHROMOSOMAL CELL implantation mutation LOCUS induction CATARACT INHERITED AFFECTING quantify
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Model for Bidding and Tendering with Bill of Quantities Based on Bid-Winning Estimate at Reasonable Low Price 被引量:2
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作者 宋吉荣 钟胜 郭耀煌 《Journal of Southwest Jiaotong University(English Edition)》 2006年第4期387-393,共7页
The possibility and rationality of introducing an bid-winning estimate based on a reasonable low price into construction bidding mode with bill of quantities were analyzed by setting up a model for bidding and tenderi... The possibility and rationality of introducing an bid-winning estimate based on a reasonable low price into construction bidding mode with bill of quantities were analyzed by setting up a model for bidding and tendering, and the functions of the estimate of reasonable low price in the bidding were revealed. On this basis, a new bidding mode of the project with bill of quantities was pro- posed. The application of the new mode will be advantageous to the promotion of the bill of quantities in China. 展开更多
关键词 Bill of quantifies Reasonable low price Model for bidding and tendering
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A novel model to evaluate spatial structure in thinned conifer-broadleaved mixed natural forests 被引量:1
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作者 Hui Liu Xibin Dong +3 位作者 Yuan Meng Tong Gao Liangliang Mao Ran Gao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1881-1898,共18页
In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structur... In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structure based on weighted Voronoi diagrams is proposed.In particular,we provide a novel methodological model for the comprehensive evaluation of the spatial structure of forest stands in natural mixed conifer-broadleaved forests and the formulation of management decision plans.The applicability of the rank evaluation and the optimal solution distance model are compared and assessed for different standard sample plots of natural mixed conifer-broadleaved forests.The effect of crown width on the spatial structure unit of the trees is observed to be higher than that of the diameter at breast height.Moreover,the influence of crown length is greater than that of tree height.There are nine possible spatial structure units determined by the weighted Voronoi diagram for the number of neighboring trees in the central tree,with an average intersection of neighboring crowns reaching 80%.The rank rating of natural forest sample plots is correlated with the optimal solution distance model,and their results are generally consistent for natural forests.However,the rank rating is not able to provide a quantitative assessment.The optimal solution distance model is observed to be more comprehensive than traditional methods for the evaluation of the spatial structure of forest stands.It can effectively reflect the trends in realistic stand spatial structure factors close to or far from the ideal structure point,and accurately assesses the forest spatial structure.The proposed optimal solution distance model improves the integrated evaluation of the spatial structure of forest stands and provides solid theoretical and technical support for sustainable forest management. 展开更多
关键词 Weighted Voronoi diagram Optimal distance model Spatial structure quantifi cation Thinning intensity Conifer-broadleaved mixed natural forests
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Landscape Structural Indicators as a Tool to Assess Land Use Changes in Planning for Sub-Basin Sustainability (Southeastern Brazil) 被引量:2
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作者 Angela Terumi Fushita José Eduardo dos Santos +2 位作者 Imyra Maíra Martins de Souza Eduarda Romanini Rômulo Theodoro Costa 《Journal of Water Resource and Protection》 2016年第4期482-492,共11页
Land use is shaped by the interactions between nature and society, and these interactions can inhibit environmental sustainability and deplete the natural capital that provides the ecosystem services upon which humans... Land use is shaped by the interactions between nature and society, and these interactions can inhibit environmental sustainability and deplete the natural capital that provides the ecosystem services upon which humans depend. Urbanity Index and Landscape Vulnerability Indicator have been proposed to improve the impact interpretability of land use changes on sub-basin sustainability for local scenarios of biodiversity conservation. A time series of LandSat 5 Thematic Mapper remote sensing data from S&#227o Carlos municipality, Southeastern Brazil, for the years 1989, 2004 and 2014 revealed that land use changes in the sub-basins do not take place in a progressive and gradual way. Over the 25-year period, the main trends showed the loss and increase of forest cover so that it has remained quantitatively similar over time due to reduced agricultural land use. The aggregation of both indicators enabled the identification of greater naturalness and lower vulnerability, as well as lower naturalness and higher vulnerability under local sub-basin conditions, pointing the need for different strategies for sub-basin biodiversity conservation and sustainability. These preliminary scenarios provide a way to communicate problems of environmental sustainability at different landscape scales to the scientific community as well as to planners, policy makers and the broader public. 展开更多
关键词 Land Use Quantifiable Indicator Urbanity Index Landscape Vulnerability Indicator
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Modeling and Dynamic Analysis for the Foundation of a Blade-Rotor System 被引量:2
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作者 Liang Anyang Huang Guoyuan +1 位作者 Zhang Yuetong Yue Lin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第3期326-332,共7页
In order to achieve the model-based fault monitoring and diagnosis,an accurate model for the rotor system is necessary to locate and quantify faults.Since the dynamic characteristics of a blade-rotor system is influen... In order to achieve the model-based fault monitoring and diagnosis,an accurate model for the rotor system is necessary to locate and quantify faults.Since the dynamic characteristics of a blade-rotor system is influenced by foundation flexibility,the modeling and dynamic analyses on the foundation were sequentially investigated.Firstly,the effect of element size on the model convergence was investigated using the forward difference quotient as the slope of the frequency difference,which found that the model converged when the element size refined to 4mm.Secondly,a modal analysis and a harmonic response analysis were performed to obtain the dynamic characteristics of the foundation structure.Finally,an optimization to the foundation utilizing an additional stiffener was conducted to reduce the foundation response and make the critical speed far away from the working frequency band of 20—50Hz. 展开更多
关键词 rotor refined sequentially utilizing blade quantify quotient harmonic convergent locate
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