旋转采样机粒度偏析机理

本文建立了旋转类采样机包含皮带中部采样机、旋斗采样机、旋转缩分机、旋管缩分机的通用数学模型,推导了截取料流时的轨迹方程、速度方程、最大速度波动公式、最大面积波动公式,从数学分析角度阐述了粒度偏析机理,找到了减少粒度偏析及提高采样精度的有效途径。     

Acoustic emission characterization of steel in H2S solution subjected to tensile load

Abstract

This paper investigates the characteristics of acoustic emission (AE) signals generated from hydrogen induced cracking (HIC) and sulfide stress corrosion cracking (SSCC) for a medium strength steel in hydrogen sulfide (H₂S) solution. The experiments performed in this study include the constant load test (CLT) and the constant extension rate test (CERT).

From the results of the CLT, the AE count rate caused by SSCC was found to be much higher than that resulted from the HIC; and the increase of the AE count rate was observed to be approximately proportional to the increase of the applied loading. In addition, the AE frequency distribution diagrams obtained from these tests were found to contain potential information for distinguishing the mechanisms of HIC and SSCC. From the results of CERT, the AE signals detected from the specimens tested in the H₂S solution were compared with those obtained from the specimens tested in the air. In addition, the AE count rate detected from the tensile specimens was studied according to the different deformation stages of the specimens. From this study, the variation of the AE count rate in each deformation stage was described.     

AN ALTERNATIVE PERSPECTIVE ON FUZZY SET-BASED APPROXIMATE REASONING

Abstract

On the subject of fuzzy set-based approximate reasoning, this paper attempts to present a perspective that is both rigorously stated and different from the standard approach as stated by Mamdani and many others. Functionally speaking, this alternative perspective produces results essentially the same as the standard one, and in fact we intend to prove that subject to certain assumptions the results will be exactly die same. We feel however that the alternative perspective offers advantages in that it makes a more appropriate and more understandable use of such concepts as fuzzy relations, the extension principle, and fuzzy composition. If indeed it can lead to a clearer and more widespread understanding of the approximate reasoning formalism then this could conceivably spark broader interest in fuzzy control and other applications.     

Development of Computer Code SAFFRON for Evaluating Breached Pin Performance in FBR's

In order to evaluate the breached pin behavior in FBR, the breached pin performance analysis code SAFFRON was developed. Based on the results of run-beyond-cladding-breach test in EBR-II as a collaborative program between PNC and U.S. DOE, the following behaviors were taken into cosideration; fuel sodium reaction product (FSRP) formation, resultant fuel expansion, breach extension of cladding and release of delayed neutron precursors into the coolant. Using 3-dimensional elastic analyses by finite element method, breached pin diameter increase is adequately predicted with the reduced Young's modulus of the breached fuel. The delayed neutron signal response in on-line diagnosis was evaluated in relation to the growth of FSRP and breached area enlargement.     

Cluster ensembles: A survey of approaches with recent extensions and applications

Cluster ensembles have been shown to be better than any standard clustering algorithm at improving accuracy and robustness across different data collections. This meta-learning formalism also helps users to overcome the dilemma of selecting an appropriate technique and the corresponding parameters, given a set of data to be investigated. Almost two decades after the first publication of a kind, the method has proven effective for many problem domains, especially microarray data analysis and its down-streaming applications. Recently, it has been greatly extended both in terms of theoretical modelling and deployment to problem solving. The survey attempts to match this emerging attention with the provision of fundamental basis and theoretical details of state-of-the-art methods found in the present literature. It yields the ranges of ensemble generation strategies, summarization and representation of ensemble members, as well as the topic of consensus clustering. This review also includes different applications and extensions of cluster ensemble, with several research issues and challenges being highlighted.     

Electrical disintegration and micro-focus X-ray CT observations of cement paste samples with dispersed mineral particles

Electrical disintegration is an effective liberation technique in mineral processing where the liberation ratio depends on the mineralogical properties of the mineral grains. However elucidation of the liberation behavior is difficult since the fragments after the electrical disintegration are fine and complex. This study applies electrical disintegration to cement paste samples with various dispersed mineral particles (calcite, quartz, albite, and pyrite) and the disintegrated products are observed with a micro-focus X-ray CT scanner. Current channels and crack extension behavior from the channels are identified by cross sectional CT and three dimensional reconstructed images. A classification of the crack patterns was carried out and compared with the results of liberation ratio measurements of the products.     

A framework for identifying differences and similarities in the managerial competencies associated with different modes of product life extension

It has been noted in the past that economically sound, environmentally preferable life extension modes such as remanufacturing and recycling have special characteristics that complicate the management of their production, logistics and associated operations. This paper considers these complicating characteristics from the perspective of the nine different modes of product life extension. In doing so, a framework and guide is provided to what issues, resource requirements and management capabilities are required for specific life extension modes. This framework provides guidance to practitioners and academics on commonalities between different product life extension modes, thereby assisting practitioners in leveraging current internal skills and capabilities and researchers in determining the generalizability of research.     

331省道盱眙段扩建工程梁项水库占用工程技术要点初探

331省道盱眙绕城段改扩建工程施工直接影响到梁项水库蓄水、防洪与大坝堤身安全,本文分步骤祥述了梁项水库施工占用水库库容及附属工程补偿技术要点和解决方案。     

客车水栓压力在线监控系统的应用及推广

针对铁路客车上水栓的现状及特点,设计出一套客车水栓压力在线监测及故障自动切除系统,并分析了使用该系统的必要性,介绍了该系统可实现的功能,对该系统的关键技术及监控组态软件设计作了详细论述,以促进其推广应用。     

球罐安全阀接管裂纹检验研究

本文讨论了球罐上出现的裂纹的成因,发现未焊透可以产生裂纹,提出维修技术方案,说明球罐制造、安装、监督检验注意事项。