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Floating Production Platforms and their Applications in the Development of Oil and Gas Fields in the South China Sea

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Journal of Marine Science and Application 2014年第1期13卷 67-75页

作者： Dagang Zhang Yongjun Chen Tianyu Zhang DMAR Engineering Inc. Beijing DMAR Ocean Tech Inc.

This paper studies the current available options for floating production platforms in developing deepwater oil fields and the potential development models of future oil and gas exploration in the South China Sea. A detailed review of current deepwater platforms worldwide was performed through the examples of industry projects, and the pros and cons of each platform are discussed. Four types of platforms are currently used for the deepwater development: tension leg platform, Spar, semi-submersible platform, and the floating production system offloading. Among these, the TLP and Spar can be used for dry tree applications, and have gained popularity in recent years. The dry tree application enables the extension of the drilling application for fixed platforms into floating systems, and greatly reduces the cost and complexity of the subsea operation. Newly built wet tree semi-submersible production platforms for ultra deepwater are also getting their application, mainly due to the much needed payload for deepwater making the conversion of the old drilling semi-submersible platforms impossible. These platforms have been used in different fields around the world for different environments; each has its own advantages and disadvantages. There are many challenges with the successful use of these floating platforms. A lot of lessons have been learned and extensive experience accumulated through the many project applications. Key technologies are being reviewed for the successful use of floating platforms for field development, and potential future development needs are being discussed. Some of the technologies and experience of platform applications can be well used for the development of the South China Sea oil and gas field.

关键词： floating platform deepwater development oil fielddevelopment deepwater technology platform host

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Localized CO_2 laser bonding process for MEMS packaging

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中国有色金属学会会刊：英文版 2006年第B2期16卷 577-581页

作者： SUN Li A. P. MALSHE S. CUNNINGHAM A. MORRIS Department of Mechanical Engineering University of Arkansas Fayetteville AR 72701 USA wiSpry inc. Irvine CA 92618 USA wiSpry inc. Cary NC 27513 USA

The packaging poses a critical challenge for commercialization of MEMS products. Major problems with the packaging process inc.ude degraded reliability caused by the excess stress due to thermal mismatch and altered performance of the MEMS device after packaging caused by thermal exposure. The localized laser bonding technique for ceramic MEMS packaging to address above-mentioned challenges was investigated. A continuous wave CO2 laser was used to locally heat sealing material for ceramic MEMS package lid to substrate bonding. To determine the laser power density and scanning speed, finite element analysis thermal models were constructed to simulate the localized laser bonding process. Further, the effect of external pressure at sealing ring on the bonding formation was studied. Pull testing results show that the scanning speed and external pressure have significant influence on the pull strength at the bonding interface. Cross-sectional microscopy of the bonding interface indicates that the packages bonded with relatively low scanning speed and external pressure conditions have higher bonding quality. This research demonstrates the potential of localized laser bonding process for ceramic MEMS packaging.

关键词：微电子机械系统 MEMS 封装局部激光焊接过程有限元分析

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Commercial Application of UFR to VRDS Unit Expansion at Qilu Petrochemical Company

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China Petroleum Processing & Petrochemical Technology 2007年第4期9卷 7-11页

作者： Sun Lili Sinopec Engineering inc. Beijing 100011

Technology and commercial application of UFR to VRDS unit expansion at Qilu Petrochemical Company, for which engineering work was done by SINOPEC Engineering inc.rporation （the former Beijing Design Institute）, were introduced. Successful experience for the first commercial application of up-flow reactor technology and debottlenecking of the unit were summarized. The findings revealed a new route for inferior residue hydrotreating and revamping the existing units of the like.

关键词： residue hydrodesulfurization reactor design revamping

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On Peer-Assisted Data Dissemination in Data Center Networks: Analysis and Implementation

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Tsinghua Science and Technology 2014年第1期19卷 51-64页

作者： Yaxiong Zhao Jie Wu Cong Liu Google inc. Temple University Sun Yat-Sen University

Data Center Networks （DCNs） are the fundamental infrastructure for cloud computing. Driven by the massive parallel computing tasks in cloud computing, one-to-many data dissemination becomes one of the most important traffic patterns in DCNs. Many architectures and protocols are proposed to meet this demand. However, these proposals either require complicated configurations on switches and servers, or cannot deliver an optimal performance. In this paper, we propose the peer-assisted data dissemination for DCNs. This approach utilizes the rich physical connections with high bandwidths and mutli-path connections, to facilitate efficient one-to-many data dissemination. We prove that an optimal P2P data dissemination schedule exists for FatTree, a specially- designed DCN architecture. We then present a theoretical analysis of this algorithm in the general multi-rooted tree topology, a widely-used DCN architecture. Additionally, we explore the performance of an intuitive line structure for data dissemination. Our analysis and experimental results prove that this simple structure is able to produce a comparable performance to the optimal algorithm. Sinc. DCN applications heavily rely on virtualization to achieve optimal resource sharing, we present a general implementation method for the proposed algorithms, which aims to mitigate the impact of the potentially-high churn rate of the virtual machines.

关键词： data center networks cloud computing P2P scheduling peer-assisted data dissemination

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A History of Fischer-Tropsch Wax Upgrading at BP-from Catalyst Screening Studies to Full Scale Demonstration in Alaska

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Journal of Natural Gas Chemistry 2006年第1期15卷 1-10页

作者： John P. Collins Joep J. H. M. Font Freide Barry Nay BP Exploration America inc. BP Exploration Operating Company

Conversion of Fischer-Tropsch wax into high quality synthetic crude or finished transportation fuels such as premium diesel has been studied over the past 15 years within BP. Catalyst screening and selection was carried out in dedicated micro-reactors and pilot plants, whose designs are critical to the performance selection. Variation in catalyst composition and defining the gas to oil feed ratios with the operating temperature are a few of the parameters studied. Product selection and maximizing diesel yield combined with stability （catalyst life） were the ultimate drivers. The selected catalyst was then tested under commercial conditions in a dedicated 300 barrel per day demonstration plant. The products were also tested in engines to assess their combustion characteristics.

关键词： Fischer-Tropsch wax upgrading hydrocracking synthetic crude diesel naphtha engine emission

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Next-generation lithography for 22 and 16 nm technology nodes and beyond

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Science China(Information Sciences) 2011年第5期54卷 959-979页

作者： WU Banqiu Applied Materials, inc., Building 81, M/S 81311, 1285 Walsh Ave, Santa Clara, CA 95050, USA Applied Materials Inc. Santa Clara USA

In this paper, next-generation lithography (NGL) for the 22 and 16 nm technology nodes and beyond is reviewed. A broad range of topics, inc.uding history, technologies, critical challenges, and the most plausible candidates are discussed. The 22 and 16 nm technology nodes rely on NGL. NGLs have been extensively studied. Because of technological issues, the semiconductor industry has stopped pursuing several NGLs, such as X-ray proximity lithography, ion projection lithography, and scattering with angular limitation projection electron lithography. Currently, the primary candidate technologies are extreme ultraviolet lithography (EUVL), maskless lithography (ML2), and nanoimprint lithography (NIL), with EUVL being the leading candidate. Sinc. EUVL was first proposed in 1988, many studies have been conducted. Currently, there is no "show stopper" for EUVL. Moreover, challenges are present in almost all aspects of EUVL technology. Almost all primary semiconductor manufacturing companies plan to implement commercial pre-production step-and-scan exposure tools in 2011. However, EUVL power at an intermediate focusing level has not yet met the volume manufacturing requirements. EUVL resists have been significantly improved recently, but there is still a critical need to meet requirements on resolution, line width roughness, and sensitivity. Creating a defect-free EUVL mask is another obstacle to the application of EUVL. ML2 and NIL, like EUVL, have also undergone significant progress recently, but throughput, defect control, and cost remain the critical impediments for practical application.

关键词： lithographic NGL XPL IPL NIL

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DEVELOPMENT　OF　inc.NEL~　ALLOY　783，A　LOW　THERMAL　EXPANSION，CRACK　GROWTH　RESISTANT　SUPERALLOY

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 503-507页

作者： J.H.Thndermann(inc. Alloys International, inc., Huntington, WV 25705, USA ) inc. Alloys Int inc. Huntington United States

Low thermal expansion superalloys have been used for a number of years in a variety of applications, inc.uding gas turbine engines. The low thermal expansion characteristics of the most widely used class of materials are derived from the ferromagnetic characteristics of Ni, Fe, and Co-based austenitic matrices containing little or no *** developments have been aimed at improving the oxidation resistance and stress accelerated grain boundary oxygen (SAGBO) *** alloy 783 is an oxidation resistant, low coefficient of thermal expansion superalloy developed for gas turbine applications. Alloy 783 represents a culmination in the development, of an alloy system with very high alumtnum content that, in addition to forming γ′,causes βaluminide phase precipitation in the austenitic *** type of structure can be processed to resist both SAGBO and general oxidation,while providing low thermal expansion and useful mechanical properties up to 700℃.Key aspects of the alloy's development are presented.

关键词： coefficient of thermal expansion oxidation resistance crack growth resistance,SAGBO inc.NEL alloy 783,alloy 718,gamma prime phase beta phase

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Optimal chunk caching in network coding-based qualitative communication

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Digital Communications and Networks 2022年第1期8卷 44-50页

作者： Lijun Dong Richard Li Futurewei Technologies inc. 2330 Central ExpresswaySanta Clara95050USA

Network processing in the current Internet is at the entirety of the data packet,which is problematic when encountering network *** newly proposed Internet service named Qualitative Communication changes the network processing paradigm to an even finer granularity,namely chunk level,which obsoletes many existing networking policies and schemes,especially the caching algorithms and cache replacement policies that have been extensively explored in Web Caching,Content Delivery Networks(CDN)or Information-Centric Networks(ICN).This paper outlines all the new factors that are brought by random linear network coding-based Qualitative Communication and proves the importance and necessity of considering them.A novel metric is proposed by taking these new factors into *** optimization problem is formulated to maximize the metric value of all retained chunks in the local storage of network nodes under the constraint of storage limit.A cache replacement scheme that obtains the optimal result in a recursive manner is proposed *** the help of the introduced intelligent cache replacement algorithm,the performance evaluations show remarkably reduced end-to-end latency compared to the existing schemes in various network scenarios.

关键词： Internet Qualitative communication New IP Chunk caching Random linear network coding End-to-end latency Cache replacement policy Degree of freedom Distance Packet size

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Corrosion Study of Base Material and Welds of a Ni-Cr-Mo-W Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 326-332页

作者： Ajit Mishra Haynes International Inc. 1020 West Park AvenueKokomo IN 46904 USA

Alloys containing chromium （Cr） and molybdenum （Mo）, as the major alloying elements, are widely used in various industries where the material experiences corrosive environments. Chromium （Cr）, when added in an optimum amount, forms a Cr203 passive film which protects the underlying metal in aggressive solutions. Molybdenum （Mo） forms its oxides in the low pH solutions, thus, enhances the uniform corrosion resistance of an alloy in reducing acids and assists in inhibition to localized corrosion. Minor alloying elements, like tungsten （W） and copper （Cu）, also improve the overall corrosion resistance of an alloy in specific solutions. In the present study, corrosion resistance behavior of commercial iron- based alloys （316L SS, 254 SMO and 20Cb3） and nickel-based alloys （Mone1400, Alloy 625 and C-276） was studied in the acidic solutions. While the corrosion behavior of wrought alloys has been widely studied, there is little to no information on the corrosion performance of their welds, typically being the weak regions for corrosion initiation and propagation. Therefore, an attempt was undertaken to investigate the uniform and localized corrosion performance of base metal, simulated heat-affected zone and all-weld-metal samples of a Ni-Cr-Mo-W alloy, C-276. The study was conducted in aggressive acidic solutions. Various corrosion and surface analytical techniques were utilized to analyze the results.

关键词： Iron-chromium-molybdenum Nickel-chromium-molybdenum-tungsten All-weld-metal Heat-affected-zone Acids Acidified ferric chloride Potentiodynamic Scanning electronmicroscopy (SEM)

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Robust model selection for positive and unlabeled learning with constraints

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Science China(Information Sciences) 2022年第11期65卷 94-106页

作者： Tong WEI Hai WANG Weiwei TU Yufeng LI Department of Computer Science and Technology Nanjing University 4Paradigm inc.

Positive and unlabeled(PU) learning is the problem in which training data contains only PU samples. Although PU learning is widely used in real-world applications, its model selection remains challenging. Specifically, traditional model selection methods are often highly sensitive to the class prior as well as the data size, resulting in human overhead in hyperparameter optimization. In this paper, we present a method called ODE(robust model selection) for robust model selection in PU learning. Two novel model evaluators based on the integral probability metric and area under the curve, which are free of the class prior, are introduced, and a variance reduction method is further employed to improve the quality of model selection. In addition, we perform model selection under user-defined constraints and propose a fast halvingstyle searching algorithm to efficiently identify the most promising model configuration. Extensive empirical studies demonstrate that our proposed method performs more robustly and is more computationally efficient than many state-of-the-art methods.

关键词： positive and unlabeled learning model selection automated machine learning

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