Failure Rule Research Articles

Research on the Tools' Strength in the Condition of Uncommonly Dynamic Heavy-Duty Loads

ntroducing the machining-ability of the surface of hydrogenated cylindrical shells blank, and the analysis showed that one of the main macroscopic factors which caused the tool to be broken early was forging defect. According to researching on both failure mechanisms and rules of the heavy-duty turning tools fracture, the conclusions that the dynamic load led into the crack then made the tool to be broken could be drawn. Then, the finite element simulation was utilized to analyze the tools working state under dynamic load condition, and the simulation results verified the correctness of the conclusion. For improving production efficiency and providing a reference for the prediction of tool breakage, finally, the critical time model of tool breakage under the condition of dynamic cutting was built, and the measures of preventing tools premature failure were developed.

Developing healthcare rule-based expert systems: Case study of a heart failure telemonitoring system

BackgroundThe use of expert systems to generate automated alerts and patient instructions based on telemonitoring data could enable increased self-care and improve clinical management. However, of great importance is the development of the rule set to ensure safe and clinically relevant alerts and instructions are sent. The purpose of this work was to develop a rule-based expert system for a heart failure mobile phone-based telemonitoring system, to evaluate the expert system, and to generalize the lessons learned from the development process for use in other healthcare applications. MethodsSemi-structured interviews were conducted with 10 heart failure clinicians to inform the development of a draft heart failure rule set for alerts and patient instructions. The draft rule set was validated and refined with 9 additional interviews with heart failure clinicians. Finally, the clinical champion of the project vetted the rule set. The concerns voiced by the clinicians during the interviews were noted, and methods to mitigate these concerns were employed. The rule set was then evaluated as part of a 6-month randomized controlled trial of a mobile phone-based heart failure telemonitoring system (n=50 for each of the telemonitoring and control groups). ResultsThe developed expert system generated alerts and instructions based on the patient's weight, blood pressure, heart rate, and symptoms. During the trial, 1620 alerts were generated, which led to various clinical actions including 105 medication changes/instructions. The findings from the trial indicated the rule set was associated with improved quality of life and self-care. ConclusionsA rule set was developed with extensive input by heart failure clinicians. The results from the trial indicated the rule set was associated with significantly increased self-care and improved the clinical management of heart failure. The developed rule set can be used as a basis for other heart failure telemonitoring systems, but should be validated and modified as necessary. In addition, the process used to develop the rule set can be generalized and applied to create robust and complete rule sets for other healthcare expert systems.

Automatic HVAC fault detection and diagnosis system generation based on heat flow models

This article introduces a new graph-based modeling methodology called heat flow modeling (HFM) for the purpose of mapping building information model (BIM) of HVAC systems automatically into fault detection and diagnosis (FDD) systems that can be integrated into HVAC control systems. The goal is an efficient and effective support of the maintenance of HVAC systems to detect and locate faults that may reduce energy efficiency, user comfort, or system lifetime. The nodes of the HFM model have a one-to-one relationship with HVAC system components and related building entities. The nodes are connected by arcs that model the flows in the HVAC systems, e.g., air, water, and information flows. The functionality of the nodes includes state variable estimations and failure rule evaluations. The failure rule outputs can be fed to an associative network based diagnosis engine to locate the faults. Since HFM nodes are instances of generic classes derived from small libraries, HVAC FDD systems can be automatically generated. The simulation result has shown the effectiveness of a proposed FDD approach and two software prototypes demonstrating the reduced engineering effort of fault detection for a small bank HVAC system.

Computational approach using Johnson–Cook model on dual phase steel

In this research, two different hypo-eutectoid steels with different carbon content and alloying elements were made into samples with dual phase ferrite martensite microstructure. Their morphology and the mechanical properties were then compared. Computational model varying the ferrite percentage was also proposed. The model adopts the failure rule of Johnson–Cook’s. The result shows that the difference in mechanical property was not only due to the variation of the ferrite parts in them but also due to the shapes of the constituents. It tends to follow the continuum mechanics rule. It is also concluded that modeling using two-dimensional approach is sufficient to estimate the properties of the dual phase structure.

Energy conversion analysis and performance research on a cone-type dielectric electroactivepolymer generator

As a type of intelligent material, dielectric electroactive polymer (DEAP) has shownconsiderable promise for energy harvesting purposes as well as in actuator mode.Theoretical analysis on DEAP generators is important to guide the optimization anddesign of a DEAP generator. In this paper, firstly, four working phases of a DEAPgenerator and energy conversion between mechanical energy input and electrical energygenerated have been studied. Then, the model of a cone-type DEAP generator isestablished. On the basis of that, some key issues of a DEAP generator, such ascapacitance, force–displacement relationship, distribution of stress and stretch ratio in themembrane, have been achieved by solving the differential and algebraic equations. It isdemonstrated that the stretch displacement of a DEAP generator and bias voltage are themain factors influencing the amount of electrical energy generated and the efficiency ofenergy conversion. In addition, the failure rule of a DEAP generator has alsobeen discussed. Finally, the proposed model is proved by experimental results,which shows the model is reliable for analyzing the cone-type DEAP generator.

Composite Material Pressure Vessel Design Research

Some composite material characteristics are summarized and main advantages of composite material are analyzed in the paper. In addition, stress analysis methods, failure rules and design techniques of a pressure vessel are also recommended. Finally, the importance of composite material has been summed up . The paper has some reference values to investigation of a composite material pressure vessel.

Module-based Failure Propagation (MFP) model for FMEA

Failure mode and effect analysis (FMEA) is one of the most important activities in the quality management of product design. Within the field of product development domain, FMEA is regarded as a key driver for product quality improvement and cost reduction. There have been various FMEA approaches considering several aspects such as knowledge management, criticality analysis, and product structure or function model to conduct more effective and systematic FMEA. But previous approaches are generally based on an ad hoc model so that they have limitations such as insufficient identification on failures, low reusability of previous FMEAs, poor understanding on failure information, high dependency of expert knowledge on failure propagation, and so on. To overcome these limitations, this study proposes a formalized function model for FMEA, which is named module-based failure propagation (MFP) model. The MFP model is proposed based on the function behavior state scheme. The MFP model consists of function decomposition tree model, configuration flow graph model, function rule, and failure rule. This study describes how to build the MFP model and introduces how to carry out FMEA with the proposed MFP model. To show the benefit of the proposed MFP model, a FMEA case study on a car air purifier is performed.

Fatigue Life Assessment for Metallic Structure: A Case Study of Shell Structure under Variable Amplitude Loading

his study presents an analysis technique to asses the fatigue life of a shell structure under variable amplitude loadings (VAL). For this purpose, the finite element analysis technique was used for the simulation works. The life prediction results are useful for improving the component design methodology at the early developing stage especially for shell structures such as a pressure vessels or pipelines analysis. The fatigue life prediction was performed using the finite element based fatigue analysis codes. In addition the ability of stress-life (S-N) and strain-life (e-N) approaches to correlate and predict life are examined according to the different damage and failure rules. Numerical life prediction results (S-N and e-N) of shells under VAL, as well as Constant Amplitude Loading (CAL) are presented and discussed. The effect of the mean stress, surface finish and the shell thickness are studied and discussed as apart of the interactions between geometries, loadings and materials. The simulation results showed that more studies on the shell structure need to be performed in order to obtain more accurate fatigue life.

Description of concrete durability damage process

Based on the damage mechanics, the concrete damage grade of relative stable environment in measurable spatial is constructed in this paper, and the concrete damage evolving model and corresponding failure rule is constructed based on the damage grade fore-defined. Therefore, the concrete health status and the residual life-span can be assessed according to the measured damage grade. It is propitious to drive the development of concrete durability assessment and life-span forecast. Its feasibility of concrete damage process description and health assessment is validated with the example in this paper, in which the damage state is described with the ultrasound velocity attenuation, and the freeze-thaw process is regarded as the concrete durability degradation influencing factor to reflect the concrete durability degradation process.

1011 金属の塑性変形を考慮した複合材/金属積層材の力学的挙動(S88-2 宇宙構造・材料(2),S88 宇宙構造・材料)

Fiber/metal composites are expected to be a material for aerospace airframe application because of its higher performance and functionally excellent characteristics. And various kind of material combination of FRP and metal has been developed aiming at practical use. In this report, we examine the influence of plastic deformation of Ti foil on the strength of Ti/CFRP fiber/metal composites. Applying a failure rule of FRP, the strength of the material was evaluated by using simple formulation based on a lamination theory and non-linear incremental calculation. And the mechanical performance of this material was examined mainly from the viewpoint of specific strength.

Damage and failure rule of rock undergoing uniaxial compressive load and dynamic load

For understanding the damage and failure rule of rock under different uniaxial compressive loads and dynamic loads, tests on red sandstone were carried out on Instron 1342 electro-servo controlled testing system with different uniaxial compressive loads of 0, 2, 4 and 6 MPa. It is found that peak stress, peak strain, elastic modulus and total strain energy decrease with the increase of static compressive stress. Based on the test results, the mechanism on damage and failure of rock was analyzed, and according to the equivalent strain hypothesis, a new constitutive model of elastic-plastic damage was established, and then the calculated results with the established model were compared with test results to show a good agreement. Furthermore the rule of releasing ratio of damage strain energy was discussed.

Non-local failure and damage evolution rule : Application to a dilatant crack model

A non-local crack propagation and damage evolution criteria were discussed in detail by the authors in [13-15] and applied to predict crack initiation from sharp notches and damage accumulation for complex cyclic loading programs. In the present paper the non-local condition is applied to the case of a cracked body subjected to compression and shear fractions inducing frictional slip and dilatancy at crack interfaces. The crack propagation directions with critical loading conditions are obtained taking into account the crack asperity interaction and dilatancy induced by slip. The material strength and compliance variation can be predicted from the model.

Negation as Failure as Resolution

Providing a clean procedural semantics of the ’’Negation As Failure rule‘‘ in Logic Programming has been an open problem for some time now. This rule has been treated as a technique in nonmonotonic reasoning, not as a rule in classical logic. This paper contains a demonstration of the negation as failure rule as a resolution procedure in first-order logic. We present a sound and complete resolution scheme for negation as failure rule for the larger class of constraint logic programs. The approach is to consider a canonical partition of the completion of a definite (constraint) program into the \If and the \FI programs. We show that a negated goal, provable from the completed definite program is provable from just the \FI part. The clauses in this program have a structure dual to that of definite Horn clauses. We describe a sound and complete linear resolution rule for this fragment, and show that a resolution proof of the negated goal from the\FI part corresponds to a finite failure tree resulting from classical linear resolution applied to the goal on the \If part of the original definite program. Our work shows that negation as failure rule can be computationally efficient in the sense that the SLD-resolution on the \If part of a definite program along with the negation as failure rule is more efficient than a direct resolution procedure on the completion of that program.

SLDNF resolution with non-safe rule and fixpoint semantics for general logic programs

The SLDNF resolution ( SLD resolution with negation as failure) is often restricted to yield a safe rule, that is, negation as failure rule is adopted only in the case that the selected negative literal in each goal should be in ground. In this paper we investigate extensions of goals in SLDNF resolutions with the case of selecting non-ground negative literals. Since Shepherdson's proposal is thought of as most general [16, 18] we formally show how the success and failure sets by Sherpherdson's SLDNFS resolution are related with a fixpoint semantics, which is generalized to be concerned with atom sets involving the variables.

A Modal Approach to Negation as Failure Rule

A Modal Approach to Negation as Failure Rule

Success and failure for hereditary Harrop formulae

We introduce the foundational issues involved in incorporating the NEGATION as FAILURE (NAF) rule into the framework of first-order hereditary Harrop formulae of Miller et al. This is a larger class of formulae than Horn clauses, and so the technicalities are more intricate than in the Horn clause case. As programs may grow during execution in this framework, the role of NAF and the CLOSED WORLD ASSUMPTION (CWA) need some modification, and for this reason we introduce the notion of a completely defined predicate, which may be thought of as a localisation of the CWA. We also show how this notion may be used to define a notion of NAF for a more general class of goals than literals alone. We also show how an extensional notion of universal quantification may be incorporated. This makes our framework somewhat different from that of Miller et al., but not essentially so. We also show how to construct a Kriple-like model for the extended class of programs. This is essentially a denotational semantics for logic programs, in that it provides a mapping from the program to a pair of sets of atoms that denote the success and (finite) failure sets. This is inspired by the work of Miller on the semantics on first-order hereditary Harrop formulae. Note that no restriction on the class of programs is needed in this approach, and that our construction needs no more than ω iterations. This necessitates a slight departure from the standard methods, but the important properties of the construction still hold.

Scaling and critical phenomena in a cellular automaton slider-block model for earthquakes

The dynamics of a general class of two-dimensional cellular automaton slider-block models of earthquake faults is studied as a function of the failure rules that determine slip and the nature of the failure threshold. Scaling properties of clusters of failed sites imply the existence of a mean-field spinodal line in systems with spatially random failure thresholds, whereas spatially uniform failure thresholds produce behavior reminiscent of self-organized critical behavior. This model can describe several classes of faults, ranging from those that only exhibit creep to those that produce large events.

Graph properties for normal logic programs

The completion of a program introduced by Clark is important for giving a declarative semantics to the negation as failure rule and to SLDNF resolution. Essential for having a completeness result is the consistency of the completion. The aim of this work is to give a unifying presentation of several known classes of programs that have consistent completion. The consistency of the completion of a program P is guaranteed by some properties of the graph which represents the dependency relation between the predicate symbols of P (global dependencies), or the ground atoms of the Herbrand basis of P (local dependencies). A taxonomy of program classes which are discriminated by these properties is presented, together with a uniform presentation of the (mostly well-known) techniques of model construction for the programs of each class. In this perspective it is also easier to understand the concept of perfect model and the relation between models of the completion and circumscription.

A new SLDNF-tree

The concepts of Sldnf-derivation, Sldnf-refutation and Sldnf-tree deal with negation resolved by means of Negation as Failure rule and generalize those of Sld-derivation, Sld-refutation and Sldtree. The definitions given by Lloyd in [41, even though perfectly suitable to obtain the theoretical results of soundness and (a restricted form of) completeness of the Negation as Failure rule, are not applicable to all program and goal. In fact, a negative literal 7 A, by definition, can be chosen only if either a finitely failed Sldnf-tree or an Sldnf-refutation exists for A. As a consequence, we have no possibility to model, by means of an Sldnf-tree, many computational behaviours that, even if they can be considered somewhat “pathological”, are very common. Moreover, it is impossible to give an effect& fairness concept for this kind of Sldnf-tree because it involves an a priori

Review of Actual Proficiency-Testing Performance Under CLIA '67 (March 14, 1990) Rules: Perspective from the First Year's Data

Under the Clinical Laboratory Improvement Act of 1967 the Health Care Financing Administration's proficiency-testing requirement applies to approximately 12,000 hospital, reference, and large-clinic laboratories in the United States. The Wisconsin State Laboratory of Hygiene is approved by the Health Care Financing Administration to provide proficiency testing in all specialties and subspecialties. The focus of the program is to provide highly specialized service and support to a limited number of participants in order to assess intralaboratory performance correctly. We report the findings over the four proficiency-testing events in 1991 for the subspecialty of routine chemistry, which serves approximately 470 participants. Failure rates for individual analytes on single proficiency testing events ranged from 0% to 13%. After four events or one year, if the mandated evaluation criteria and failure rules were strictly applied, as many as 11% of the laboratories could have found themselves involuntarily suspended from offering all routine chemistry testing.