Method for Evaluating Bolt Competitive Failure Life Under Composite Excitation

In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode prediction model and“load ratio-life prediction curve”(ξ-N curve)of the bolt competitive failure are established.Given the poor correlation of theξ-N curve,an evaluation model of the bolt competitive failure life is proposed based on Miner’s linear damage accumulation theory.Based on the force analysis of the thread surface and simulation of the bolt connection under composite excitation,a theoretical equation of the bolt competitive failure life is established to validate the model for evaluating the bolt competitive failure life.The results reveal that the proposed model can accurately predict the competitive failure life of bolts under composite excitation,and thereby,it can provide guidance to engineering applications.

Green evaluation of microwave-assisted leaching process of high titanium slag on life cycle assessment

A greenness evaluation index and system of microwave-assisted leaching method were established.The effects of the life cycle assessment variables,such as the resource consumption,environment impact,cost,time and quality,were investigated,and the concept of green degree was applied in the production of synthetic rutile.An analytic hierarchy process was utilized to assess matrix of greenness evaluation.The Gauss-Seidel iterative matrix method was employed to solve the assessment matrix and obtain the weights and membership functions of all evaluation indexes.A fuzzy decision-making method was applied to build the greenness evaluation model,and then the scores of green degree in microwave-assisted leaching process was obtained.The greenness evaluation model was applied to the life cycle assessment of the microwave-assisted leaching process.The results show that the microwave-assisted leaching process has advantages over the conventional ones,with respect to energy-consumption,processing time and environmental protection.

MULTIAXIAL CREEP-FATIGUE LIFE EVALUATION UNDER PROPORTIONAL LOADING

A new method was proposed for the multiaxial creep-fatigue life evaluation under proportional loadings. Because this method was derived from the strain range partitioning method with a multiaxiality factor, it was possible to consider the influence of both creep-fatigue interaction and multiaxial stress state on fatigue life. In order to predict the combined axial-torsional fatigue life the damage under combined loading was defined as linear summation of the damages under axial loading and torsional loading. Axial-torsional creep-fatigue tests were carried out using tubular specimens of 316LC austenitic stainless steel and the ferritic rotor steel. This rotor steel was developed for the permanent magnet type eddy current retarder in heavy trucks. Experimentally obtained lives of both steels were well corresponded with the lives predicted by the proposed method. It was found that the proposed method was effective in multiaxial fatigue life evaluation under proportional creep-fatigue loadings.

Fatigue life evaluation on key components of high-speed railway catenary system

The fatigue load spectrum and operation life evaluation of key components in the catenary system under the high speed train running condition were investigated.Firstly,based on the catenary model and pantograph model,the couple dynamic equations of pantograph–catenary were built with the Lagrange’s method;then the dynamic contact force was obtained by the Newmark method at the train speeds of 250,280 and 300 km/h,respectively.Secondly,the finite element model(FEM)of one anchor section’s catenary was built to analyze its transient response under the contact force as train running;then the loading time history of messenger wire base,steady arm,registration tube,oblique cantilever,and straight cantilever were extracted.Finally,the key components’fatigue spectrum was carried out by the rain-flow counting method,and operation life was estimated in consideration of such coefficients,such as stress concentration,shape and dimension,surface treatment.The results show that the fatigue life of the catenary system reduces with the increasing of train speed;specifically,the evaluated fatigue life of the steady arm is shorter than other components.

Fatigue life evaluation of girth butt weld within welded cast steel joints based on the extrapolation notch stress method

The fatigue life evaluation of the girth butt weld within the welded cast steel joint was studied based on the extrapolation notch stress method.Firstly,the mesh sensitivity of the finite element model of the welded cast steel joint was analyzed to determine the optimal mesh size.Based on the stress field analysis of the finite element model of the welded cast steel joint at the weld toe and weld root,the sharp model of the extrapolation notch stress method was applied to derive the effective notch stress of the rounded model belonging to the effective notch stress method,in which the key problem is to calculate the extrapolation point C,and the extrapolation point C has an exponential function relationship with the geometric parameters of the welded cast steel joint.By setting different values of geometric parameters,the corresponding value of parameter C is calculated,and then the functional relationship between the extrapolation point C and the geometric parameters can be obtained by the multiple linear regression analysis.Meanwhile,the fatigue life evaluation of the girth butt weld within welded cast steel joints based on the effective notch stress was performed according to the guideline recommended by the IIW(International Institute of Welding).The results indicate that the extrapolation notch stress method can effectively simplify the process of calculating the effective notch stress and accurately evaluate the fatigue life of the girth butt weld within welded cast steel joints.

Stochastic Modelling of Vulnerability Life Cycle and Security Risk Evaluation

The objective of the present study is to propose a risk evaluation statistical model for a given vulnerability by examining the Vulnerability Life Cycle and the CVSS score. Having a better understanding of the behavior of vulnerability with respect to time will give us a great advantage. Such understanding will help us to avoid exploitations and introduce patches for a particular vulnerability before the attacker takes the advantage. Utilizing the proposed model one can identify the risk factor of a specific vulnerability being exploited as a function of time. Measuring of the risk factor of a given vulnerability will also help to improve the security level of software and to make appropriate decisions to patch the vulnerability before an exploitation takes place.

Erratum to “Recovery Approaches in Mental Health: A Qualitative Evaluation of the Whole Life Therapy Programme for Persons with Schizophrenia” [Health 5 (2013) 582-587]

The original online version of this article (Littlechild, B., Smith, A. H., Meredith-Windle, G., Gale, T., Lloyd, M. and Hawley, C. (2013) Recovery Approaches in Mental Health: A Qualitative Evaluation of the Whole Life Therapy Programme for Persons with Schizophrenia. Health, 5, 582-587. http://dx.doi.org/10.4236/health.2013.53A077) was published mistakenly with a co-author (who also developed the Whole Life Programme) missing. To reflect the contribution and responsibility of the co-author as well as the affiliations of the authors at the time of the study, we revised authorship and author affiliations of the article.

Recovery approaches in mental health: A qualitative evaluation of the Whole Life Therapy programme for persons with schizophrenia

The recovery approach within mental health services has in recent years been influential in promoting more active participation from service users concerning their treatment and progress, within a move towards models of interventions based on social models and ideas of service user empowerment. Although mental health recovery models are often heralded as ideological goals, comparatively little has been documented about the means of achieving these. This article sets out the nature and content of the Whole Life Programme, used within the Hertfordshire NHS Partnership Foundation Trust, and the results of qualitative research into the programme that set out to analyse the impact of its delivery from the perspectives of service users. The research examined the experiences and views of participants receiving treatment several months after the completion of the programme, and also of those who withdrew prematurely, in order to learn from these experiences, adding to our understanding of how one recovery based approach, the Whole Life Manual, can be applied in practice.

Sensory Evaluation of Different Packaged Roast Beef Treatments Designed for the Extension of Its Shelf Life

This study was carried out to investigate the effect of different nitrite concentrations on the sensory parameters of roast beef including color, flavor, juiciness, texture and overall acceptability. Four roast beef batches were formulated;the first three treatments were with nitrite concentrations of 0.006%, 0.012% and 0.018% and stored at abused chilling temperature (12°C), while the fourth one was a control treatment with 0.026% nitrite and storage at 4°C. Results showed that increasing nitrite concentration from 0.006% to 0.026% enhanced the shelf life of roast beef stored for 7 days without affecting the sensory characteristics whether at 12°C or 4°C since there were no significant differences (P > 0.05) between all treatments regarding color, flavor, juiciness, texture and overall acceptability. These results could direct us to use high nitrite concentration to protect this product and elongate its shelf life without affecting its preference parameters.

A Review of the Life Cycle Analysis for Plastic Waste Pyrolysis

Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions.

Operational mechanism of comprehensive benefit evaluation of existing building energy efficient renovation project based on value-added life

The comprehensive benefit evaluation of the existing building energy efficient renovation project cannot be separated from the scientific and effective evaluation mechanism.Based on the value-added life perspective,this paper analyzes the implementation subject,standard,system and principle of the comprehensive benefit evaluation of the existing building energy efficient renovation project.It plans the process of comprehensive benefit evaluation,and builds a scientific and reasonable operation platform of evaluation system,with a view to promoting the effective implementation of the comprehensive benefit evaluation of existing building energy-saving retrofits.

Prospective evaluation of health status, quality of life and clinical outcomes following implantable defibrillator generator exchange

BACKGROUND Little is known about health status and quality of life(QoL)after implantable cardioverter-defibrillator(ICD)generator exchange(GE).METHODS We prospectively followed patients undergoing first-time ICD GE.Serial assessments of health status were performed by administering the 36-Item Short Form Survey(SF-36).RESULTS Mean age was 67.5±14.3 years,left ventricle ejection fraction(LVEF)was 36.5%±15.0%and over 40%of the cohort had improved LVEF to>35%at the time of GE.SF-36 scores were significantly worse in physical/general health domains compared to domains of emotional/social well-being(P<0.001 for each comparison).Physical health scores were significantly worse among those with medical comorbidities including diabetes,chronic obstructive pulmonary disease and atrial fibrillation.Mean follow-up was 1.6±0.5 years after GE.Overall SF-36 scores remained stable across all domains during follow-up.Survival at 3 years post-GE was estimated at 80%.Five patients died during follow-up and most deaths were adjudicated as non-arrhythmic in origin.Four patients experienced appropriate ICD shocks after GE,three of whom had LVEF which remains impaired LVEF(i.e.,<35%)at the time of GE.CONCLUSION Patients undergoing ICD GE have significantly worse physical health compared to emotional/social well-being,which is associated with the presence of medical comorbidities.In terms of clinical outcomes,the incidence of appropriate shocks after GE among those with improvement in LVEF is very low,and most deaths post-procedure appear to be non-arrhythmic in origin.These data represent an attempt to more fully characterize the spectrum of QoL and clinical outcomes after GE.

Net Present Value Method: A Method Recommended by ISO 15686-5 for Economic Evaluation of Building Life Cycle Costs

The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.

A Life Evaluation System and its Application to Mining Machinery Equipment

Based on analyzing the mining equipment life evaluation theoretical system, the equipment life evaluation target system of the mining machinery is put forward taking the economic life, security life, reliability life and technical life as the targets. Then, the structure and model of the mining equipment life evaluation system are established and prepared for the realization of the system theoretically. Taking hydraulic support as the research object, the life evaluation system of hydraulic support is established and practice shows that the life evaluation system is feasible.

New LCA Approach with Fuzzy Evaluation

A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products.

Environmental impact evaluation for high-speed railway

Environmental impact evaluation system boundary of high-speed railway was defined based on the total life cycle theory,and the index system to evaluate the environmental impact of high-speed railway was established with the fuzzy analytic hierarchy method,and the matter-element evaluation model was established on the basis of the extension theory.By calculating its comprehensive interrelatedness,the evaluation rank of environment impacts of high-speed railway was determined.The numerical example shows that the model has vast prospect,which can not only expand the application areas of extension theory,but also change the traditional evaluation methods and provide new ideas and means for environmental impact evaluation of high-speed railway.

Health evaluation method for degrading systems subject to dependent competing risks

This paper proposes a health evaluation method for degrading systems subject to competing risks of dependent soft and hard failures. To characterize the time-varying degradation rate, the degradation process is determined by a non-stationary Gamma process and the soft failure is encountered when it exceeds a predefined critical level. For the hard failure, a Cox’s proportional hazard model is applied to describe the hazard rate of the time to system failure. The dependent relationship is modeled by incorporating the degradation process as a time-varying covariate into the Cox’s proportional hazard model. To facilitate the health characteristics evaluation, a discretization technique is applied both to the degradation process and the monitoring time.All health characteristics can be obtained in the explicit form using the transition probability matrix, which is computationally attractive for practical applications. Finally, a numerical analysis is carried out to show the effectiveness and the performance of the proposed health evaluation method.

Reliability Evaluation of CRH_(3C) Brake Pads Based on Bayes Method

In the reliability life evaluation of CRH_(3C) brake pads,the evaluation model of reliability life is put forward based on the Bayes method in the small sample. The correctness of evaluation model is validated by comparing and analyzing with the evaluation results based on Bootstrap simulation. Also by comparing the result with the semi-empirical method,the life evaluation results of the brake pads which are based on the Bayes method are more actual. The results which are based on the Bayes method can provide the theoretical basis and guidance for the repair and replacement of brake pads.

Evaluation for Applied Materials of Eco-technology

The eco-materials(include natural and artificial material) applied in the eco-technology in internal currently,usually lack of evaluation for applicative conditions.Hence,this study carry on the whole research and identifications to draft the eco-materials of eco-technology.The evaluation models of applied materials for eco-technology were proposed.The quantitative score were obtained by expert’s person evaluation.Three models were proposed to quantify the effects of applied materials on the ecological environment.The statistical procedures were adopted to compare the performance of these materials for eco-technology.The results indicated that the comparison of applied materials can be treated by quantitative analysis.For the further analysis,more evaluated data from expert’s experience need to be collected then the bias of person subject can be reduced.In addition to reach the benefits in the respects of ecosystem,society,economy and function,also practice the comprehensive effects in eco-technology.