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Finite element analysis of chip formation and residual stresses induced by sequential cutting in side milling with microns to sub- micron uncut chip thickness and finite cutting edge radius

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Advances in Manufacturing 2015年第4期3卷 309-322页

作者： Nejah Tounsi Tahany EI-Wardany Open Manufacturing Solutions inc. Pierrefonds QC Canada United Technologies Research Center East-Hartford CT US

In this paper, the effect of four sequential cuts in side milling of Ti6Al4V on chip formation and residual stresses （RS） are investigated using finite element method （FEM）. While the open literature is limited mainly to the studies of orthogonal sequential cutting with the constant uncut chip thickness greater than 0.01 mm, it is suggested herein to investigate not only the variable uncut chip thickness which characterises the down milling process, but also the uncut chip thickness in the sub-micron range using a finite cutting edge radius. For the resulting ductile machining regime, the characteristics of the chip mor- phology, the force profiles, the plastic deformation and temperature distributions have been analyzed. Furthermore, this study revealed that the RS should be extracted toward the area where the insert exits the workpiece in the FE simulation of the down-milling process. The simulation of a number of sequential cuts due to the consecutive engagements of the insert is required in order to capture the gradual accumulation of the RS before reaching an asymptotic convergence of the RS profile. The predicted RS are in reasonable agreement with the experimental results.

关键词： Finite element method (FEM) Down milling - Sequential cuts Ductile machining regime Chip formation Residual stresses (RS)

WHAT DOES ACCESS TO JusTICE REQUIRE？ -- OVERCOMING BARRIERS TO INVOKE THE UNITED NATIONS CONVENTION ON THE RIGHTS OF PERSONS WITH DISABILITIES

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Frontiers of Law in China-Selected Publications from Chinese Universities 2016年第2期11卷 280-322页

作者： Kevin M. Cremin Columbia Law School MFY Legal Services Inc. New York US

Persons with disabilities have a right to effective access to justice under the United Nations Convention on the Rights of Persons with Disabilities （UNCRPD）. This article provides insights on the parameters of that right, inc.uding a close examination of the history and text of Article 13, which directly addresses access to justice and other relevant UNCRPD provisions. In addition to the UNCRPD, this article discusses implementation guidance from the Committee on the Rights of Persons with Disabilities, inc.uding its guidelines for State Party reports and jurisprudence. The initial reports by eleven States Parties -- Argentina, Azerbaijan, China, Costa Rica, Croatia, Dominican Republic, Ecuador, Hungary, Mexico, Peru and Turkmenistan - are also considered. The Committee＇s feedback regarding implementation of Article 13 by these eleven States parties is critiqued for being limited and inc.nsistent. This article then attempts to clarify what effective access to justice actually requires. It does so by focusing on the insights that can be drawn from implementation of Article 13 sinc. the UNCRPD was adopted as well as implementation guidance from the Conference of States Parties, the International Disability Alliance, the World Network of users and Survivors of Psychiatry and the National Center for Access to Justice. This article concludes with recommendations on how the Committee can improve its guidance on access to justice to help ensure that equal rights will not be illusory for persons with disabilities.

关键词： access to justice Convention on the Rights of Persons with Disabilities right tocounsel Committee on the Rights of Persons with Disabilities

Iterative coupling reservoir simulation on high performance computers

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Petroleum Science 2009年第1期6卷 43-50页

作者： Lu Bo Wheeler Mary F. BP America inc. Houston TX 77079 US Department of Petroleum ＆ Geosystems Engineering The University of Texas at Austin Austin TX 78712 USA

In this paper, the iterative coupling approach is proposed for applications to solving multiphase flow equation systems in reservoir simulation, as it provides a more flexible time-stepping strategy than existing approaches. The iterative method decouples the whole equation systems into pressure and saturation/concentration equations, and then solves them in sequence, implicitly and semi-implicitly. At each time step, a series of iterations are computed, which involve solving linearized equations using specific tolerances that are iteration dependent. Following convergence of subproblems, material balance is checked. Convergence of time steps is based on material balance errors. Key components of the iterative method inc.ude phase scaling for deriving a pressure equation and use of several advanced numerical techniques. The iterative model is implemented for parallel computing platforms and shows high parallel efficiency and scalability.

关键词： Iterative coupling reservoir simulation multiphase flow phase scaling parallel scalability

100-Gb/s undersea transmission with high spectral efficiency using pre-filtered QPSK modulation format

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Chinese Optics Letters 2010年第9期8卷 831-836页

作者： J.-X. Cai Y. Cai C. R. Davidson D. G. Foursa A. Lucero O. Sinkin W. Patterson A. Pilipetskii G. Mohs Neal S. Bergano Tyco Electronics Subsea Communications LLC ("TE SubCom" formerly known as ~co Telecommunications (us) inc.) 250 Industrial Way West Eatontown NJ 07724 USA

We provide a review of our recent 100-Gb/s, high spectral efficiency （SE） experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability （MAP） detection algorithm can significantly improve SE. We transmitted 96×100-Gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed （PDM-RZ-QPSK） channels with 300% SE over 10608 km using 52-km spans of 150-μm 2 fiber and simple single-stage erbium-doped fiber amplifiers （EDFAs）. We also achieved 400% SE over 4368 km using similar techniques.

关键词： Bit error rate Erbium doped fiber amplifiers Modulation Optical signals Quadrature phase shift keying Signal processing

Molecular targeted agents—where we are and where we are going

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Chinese Journal of Cancer 2013年第5期32卷 225-232页

作者： Li Yan Merck & Co. Inc. us Chinese Anti-Cancer Association School of Oncology Peking University Cancer Hospital Beijing Cancer Hospital

A total of 23 new cancer medicines or indication expansions were approved by the U. S. Food and Drug Administration in 2012. Among these, 12 are new molecular entities (NMEs)-new chemical or biological drugs approved for the first time for oncologic use-and 10 of these NMEs are molecular targeted agents. Among the 10 targeted agents, 4 are anti-angiogenesis agents and 2 are Bcr-Abl pathway inhibitors, targeting well established targets validated by previously approved agents such as bevacizumab (Avastin) or imatinib (Gleevec). Despite this progress, several questions remain: Do these newly approved agents provide sufficient treatment options to manage the broad spectrum of cancers we deal with in the clinic? Where will the next wave of new cancer drugs come from? Where should R&D efforts be invested to continue improve cancer treatment and management, especially for tumor types uniquely prevalent in China? This editorial and the review articles in this special issue of Chinese Journal of Cancer provide an in depth review of the progress and challenges in developing targeted cancer therapies, as well as an outlook of new research areas where near term breakthroughs are expected to overcome some of these challenges.

关键词：靶向药物分子抗血管生成生物药品治疗方案抗癌药物管理局代理商

Coal pillar mechanics of violent failure in U.S. Mines

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International Journal of Mining Science and Technology 2017年第3期27卷 387-392页

作者： Maleki Hamid Maleki Technologies Inc. Spokane WA 99223 USA

This paper seeks to enhance the understanding that the horizontal stresses build up and release during coal pillar loading and unloading(post-failure) drawing upon three decades of observations, geomechanical monitoring and numerical modeling in bump-prone U.S. mines. The focus is on induced horizontal stress in mine pillars and surrounding strata as highly stressed pillars punch into the roof and floor, causing shear failure and buckling of strata; under stiff stratigraphic units of some western us mines, these events could be accompanied by violent failure of pillar cores. Pillar punching eventually results in tensile stresses at the base of the pillar, facilitating transition into the post-failure regime; this transition will be nonviolent if certain conditions are met, notably the presence of interbedded mudstones with low shear strength properties and proper mine designs for controlling seismicity and dynamic loads. The study clearly shows high confining stress build-up in coal pillars resulting in up to twice higher peak vertical stress and high strain energy accumulations in some western us mines in comparison with peak stresses predicted using common empirical pillar design methods. It is the unstable release of this strain energy that can cause significant damage resulting from pillar dilation and ground movements. These forces are much greater than the capacity of most common internal support systems, resulting in horizontal stressinduced roof falls locally, in mines under unremarkable far-field horizontal stress. Attention should be placed on pillar designs as inc.easing support density may prove to be ineffective. This mechanism is analyzed using field measurements and generic finite-difference stress analyses. The study confirms the higher load carrying capacity of confinement-controlled coal seams in comparison with structurally controlled coal seams. Such significant differences in confining stresses are not taken into account when estimating peak pil

关键词： Rockburst and coal bumps Field measurements Stress analysis Mechanics Horizontal stress

Tracer Testing Strategies for Effective Design and Implementation of in Situ Groundwater Remediation

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Journal of Environmental Science and Engineering(A) 2013年第12期2卷 759-769页

作者： Anil Waduge Elizabeth Cohen Craig Divine arcadis EC Harris UK Limited Newmarket CB8 7FA United Kingdom arcadis us Incorporated. Novi Michigan 48377 USA arcadis us Incorporated Irvine California 92602 USA

The effectiveness of an injection-based remediation strategy is primarily governed by accurate understanding of reagent delivery and ensuring uniform distribution within the reactive zone. In IRZ （in situ reactive zone） design, the required reagent strength, injection volumes, injection rates, injection frequency, injection and monitoring well spacing, and the cost and time to achieve remediation goals are governed by the hydrogeology of the site. A properly designed tracer test is capable of providing critical above mentioned site-specific information, to assist with full scale design of an IRZ. This paper describes that implementing tracer testing to support remedial design can result in enhanced design efficiency, added assurance in full-scale implementation and ultimately resulted in substantial cost savings. Therefore, it is recommended that the broader practitioner community adopt this technique as a best practice for effective and optimum in situ remediation system design.

关键词： Tracer testing mobile porosity in situ remediation system design.

Tools to identify the men with prostate cancer most appropriate for active surveillance？

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Asian Journal of Andrology 2014年第1期16卷 97-98页

作者： Robert H Getzenberg GTx inc. Memphis TN USA

Agreat deal of effort is underway in order .to identify those men with prostatecancer felicitous for active surveillance with greater precision than that afforded to us today. In the manuscript by Irshad et al. the authors evaluate a novel set of genes associated with senescence and aging as tools that can provide guidance regarding the indolent nature of an individual＇s prostate cancer with validation using both mRNA and protein analyses. While additional studies are required to understand the full impact of these findings, the innovative approach taken enhances our understanding of distinc. phenotypes of prostate cancer.

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Effect of Operational Changes in Reducing Fish Impingement at a Power Plant in Ohio, usA

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Journal of Environmental Science and Engineering(A) 2015年第2期4卷 55-66页

作者： Paul Henry Patrick Elaine Mason Darlene Ager Scott Brown arcadis Canada inc. (formerly arcadis SENES Canada inc.) Richmond Hill L4B3N4 Ontario Canada Kinectrics North America inc. Toronto M8Z5G5 Ontario Canada FirstEnergy Corp. Akron 44308 Ohio USA

Both intake volumetric flow and through-screen velocity （the velocity of water as it passes through the screen） are important variables affecting fish impingement at industrial water intake structures inc.uding those at power plants. However, there are limited data available on quantitative assessments of impingement following changes in power plant operation such as reduced volumetric flow and intake velocity. Impingement studies were conducted at Bay Shore Power Plant in 2005-2006 （baseline） and again in 2013-2014 following fish protection mitigation which inc.uded reduced intake volumetric flows （from 33.5 m^3·s^-1 to 9.1 cm·s^-1）, a reduced through-screen velocity （from approximately 79.2 cm·s^-1 to 11.6 cm·s^-1）, modified traveling screens and installation of a fish-return system to gently and quickly remove any fish that were impinged back into the waterbody. A comparison of baseline and post-mitigation results suggested that with this mitigation in place, impingement reductions can exceed 90% for robust dominant fish species in the area.

关键词： Impingement fish protection cooling water intake structure flow and velocity reduction mitigation.