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大规模天线阵列；信道建模；5G；阴影衰落；时延扩展；匹配滤波器；香农容量；信道状态数；信道富裕度 1

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Floating production storage and offloading systems’ cost and motion performance: A systems thinking application

Rini NISHANTH, Andrew WHYTE, V. John KURIAN

《工程管理前沿（英文）》 2018年第5卷第3期页码 357-368 doi: 10.15302/J-FEM-2018022

摘要：

Floating production storage and offloading (FPSO) units increasingly represent a practical and economic means for deep-water oil extraction and production. Systems thinking gives a unique opportunity to seek a balance between FPSO technical performance(s), with whole-cost; stakeholder decision-making is charged to align different fit-for-use design specification options’ that address technical-motion(s), with respective life-cycle cost analyses (LCCA). Soft system methodology allows situation based analyses over set periods-of-time by diagnosing the problem-at-hand; namely, assessing the antecedents of life-cycle cost relative to FPSO sub-component design alternatives. Alternative mooring- component comparisons for either new-build hulls or refurbished hulls represent an initial necessary consideration to facilitate extraction, production and storage of deep-water oil reserves. Coupled dynamic analysis has been performed to generate FPSO motion in six degrees of freedom using SESAM DeepC, while life-cycle cost analysis (LCAA) studies give net-present-value comparisons reflective of market conditions. A parametric study has been conducted by varying wave heights from 4 – 8 m to understand FPSO motion behavior in the presence of wind and current, as well as comparing the motions of turreted versus spread mooring design alternatives. LCCA data has been generated to compare the cost of such different mooring options/hull conditions over 10 and 25-year periods. Systems thinking has been used to explain the interaction of problem variables; resultantly this paper is able to identify explicit factors affecting the choice of FPSO configurations in terms of motion and whole-cost, toward assisting significantly with the front-end engineering design (FEED) phase of fit-for-purpose configured FPSOs, in waters off Malaysia and Australia.

关键词： FPSO LCCA spread/turret-mooring DeepC cost motion soft-systems

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Dynamic performance of submerged floating tunnel with different mooring styles subjected to anchor cable

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0932-7

摘要： Submerged floating tunnels (SFTs) are novel structures for transportation across long- and deep-strait regions. Owing to severe wave and current excitation as well as the effects of underwater structures and corrosion, the risk of local anchor cable failure is high, which can result in the progressive failure of the entire structure. In this study, experimental and numerical investigations are conducted to analyze the dynamic behavior of an SFT with different mooring styles under local cable failure. A custom-designed cable failure device and the birth-and-death element method are used to simulate cable failure (i.e., progressive failure) via experiments and numerical simulation, respectively. A physical-scale segmental model of an SFT with different mooring styles under anchor cable failure is developed in this study. A segmental and entire-length mathematical model is developed using the ANSYS program to perform the numerical simulation. The results of the segmental numerical and experimental models indicate good agreement. The dynamic response of an SFT with different mooring styles under cable failure is comprehensively investigated by investigating the effects of key parameters (wave period, buoyant weight ratio, and cable failure mechanism). Moreover, the progressive failure of the SFT under cable failure is investigated via a segment model test and a numerical simulation of its entire length. The present study can serve as a reference for the safer designs of the SFT mooring style.

关键词： dynamic behaviors submerged floating tunnel cable failure mooring style progressive failure

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一种新的通信抗干扰技术体制：预编码跳码扩谱

姚富强,张毅

《中国工程科学》 2011年第13卷第10期页码 69-75

摘要：

基于常规直扩体制的不足，笔者分析了跳码扩谱的必要性，提出和研究了一种新的预编码跳码扩谱通信抗干扰技术体制，重点讨论了预编码跳码扩谱的基本原理与自编码跳码扩谱的异同点、关键技术等，最后分析了其基本性能。该体制和性能已在实际中得到初步验证。

关键词：通信抗干扰直接序列扩谱预编码跳码扩谱自编码跳码扩谱

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房间之间火灾蔓延过程的网络模型

游宇航,李元洲,霍然

《中国工程科学》 2005年第7卷第7期页码 86-89

摘要：

运用网络模型（networks）对火灾在房间之间的蔓延过程进行了分析；计算不同条件下火灾沿不同路径蔓延的概率和时间，找出其中危险的因素；通过加强安全措施，对火灾蔓延过程进行了有效的控制。结果表明，应用网络模型来分析火灾在房间之间的蔓延过程，可对于蔓延的可能性和危险性作出了较好的预测。

关键词：火灾蔓延房间网络模型路径

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Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster

《环境科学与工程前沿（英文）》 2021年第15卷第3期 doi: 10.1007/s11783-021-1386-6

摘要：

• Aerosol transmission is an indispensable route of COVID-19 spread.

关键词： SARS-CoV-2 COVID-19 Environmental factor Aerosol transmission Epidemiologic characteristic

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网络病毒行为模式分析

山秀明,李旲,焦健,任勇,仇贲,曹轶群

《中国工程科学》 2003年第5卷第12期页码 55-59

摘要：

计算机网络在为人类造福的同时，也为病毒的传播提供了便利。在网络环境下，病毒传播的范围扩大了，速度大大加快，网络已成为近年来病毒传播的主要途径。针对病毒在网络上传播的新特点，分析了网络环境下病毒传播的主要模式，包括E-mail传播、主动扫描传播、通过服务器传播等，介绍了业界的一些对策，并给出了一般用户有针对性的应对措施。

关键词：病毒网络传播模式

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Construction technology on pile foundation of No. 6 main pier in Dashengguan Yangtze Bridge

Hongbin YU , Zeping LIAN ,

《结构与土木工程前沿（英文）》 2009年第3卷第3期页码 339-343 doi: 10.1007/s11709-009-0047-9

摘要： Based on pile foundation construction of No. 6 main pier, deep mudstone geological foundation and deep-water construction in Nanjing-Dashengguan Yangtze Bridge, the method of super-large-diameter bored pile in deep water is studied. The spread drill, application of PHP mud, and choice of machine are solved by adopting two machines of KTY4000 and KPG300A. Besides, the airlift reversing circulation is selected in slag discharge. The results show that this method can ensure successfully the construction of pier foundation to satisfy the demands of codes.

关键词： PHP slurry KTY4000 drilling machine KPG3000A drilling machine spread drill

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自适应最优相关间隔选择的多普勒频偏估计算法

张彭,毕光国,曹秀英,袁晓辉

《中国工程科学》 2007年第9卷第6期页码 71-76

摘要：

在信道自相关特性的多普勒频偏估计算法的基础上，分析了存在的估计性能不受信噪比和频偏变化影响的最优相关间隔。利用该特性提出一种逐次缩小搜索范围的迭代（CIO，correlation唱interval optimized）算法，实现对其搜索和最大多普勒频偏的估计。通过仿真证明理论分析的正确及算法的有效性。与传统基于相关估计算法相比，该算法自适应于信噪比和频偏变化，估计性能基本上独立于信噪比和频偏的变化，实现多普勒频偏的直接性能估计。

关键词：多普勒频偏自相关最优化迭代

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优化光学亚像素定位精度极限——揭示小PSF的像素相位效应 Article

战海洋, 邢飞, 宝竞宇, 孙婷, 陈真真, 尤政, 袁利

《工程（英文）》 2023年第27卷第8期页码 140-149 doi: 10.1016/j.eng.2023.03.009

摘要：

Subpixel localization techniques for estimating the positions of point-like images captured by pixelated image sensors have been widely used in diverse optical measurement fields. With unavoidable imaging noise, there is a precision limit when estimating the target positions on image sensors, which depends on the detected photon count, noise, point spread function (PSF) radius, and PSF’s intra-pixel position. Previous studies have clearly reported the effects of the first three parameters on the precision limit but have neglected the intra-pixel position information. Here, we develop a localization precision limit analysis framework for revealing the effect of the intra-pixel position of small PSFs. To accurately estimate the precision limit in practical applications, we provide effective PSF (ePSF) modeling approaches and apply the Cramér-Rao lower bound. Based on the characteristics of small PSFs, we first derive simplified equations for finding the best precision limit and the best intra-pixel region for an arbitrary small PSF; we then verify these equations on real PSFs. Next, we use the typical Gaussian PSF to perform a further analysis and find that the final optimum of the precision limit is achieved at the pixel boundaries when the Gaussian radius is as small as possible, indicating that the optimum is ultimately limited by light diffraction. Finally, we apply the maximum likelihood method. Its combination with ePSF modeling allows us to successfully reach the precision limit in experiments, making the above theoretical analysis effective. This work provides a new perspective on combining image sensor position control with PSF engineering to make full use of information theory, thereby paving the way for thoroughly understanding and achieving the final optimum of the precision limit in optical localization.

关键词： Optical measurement Subpixel localization Precision limit optimization Small point spread functions Centroiding Star sensors

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高晓沨：基于数据建模的疫情传播分析（2020年4月18日）

2022年08月18日

关键词：抗击疫情

为有效防控新冠病毒肺炎争取时间——抗疫假期政策对疫情传播的影响 Article

陈思邈, 陈秋实, 杨维中, 薛澜, 刘远立, 杨俊涛, 王辰, Till Bärnighausen

《工程（英文）》 2020年第6卷第10期页码 1108-1114 doi: 10.1016/j.eng.2020.07.018

摘要：

在新发突发传染病的早期阶段，快速应对对于疫情防控至关重要。用于控制疫情的公共假期能为大规模、迅速地进行社会隔离和其他举措提供关键的时间窗口期。本研究的目的是探讨抗疫假期的起始时间节点和持续时间对中国早期新冠病毒肺炎疫情传播的影响。我们开发了一个房室模型来模拟从2020年1月开始中国新冠病毒肺炎疫情的动态传播；预测并比较了春节期间在有抗疫假期和没有抗疫假期下的疫情传播；考虑了抗疫假期在不同持续时间、不同起始时间节点，以及在关于病毒传播率的不同假设下的多种情况；估计了在不同情况下达到某些感染阈值所需的天数延迟。结果表明，中国的抗疫假期使新冠病毒肺炎疫情的传播停滞了许多天。与不设抗疫假期的场景相比，基础场景的抗疫假期（湖北省为21 d，中国所有其他省为10 d）可使确诊感染100 000例的时间延迟7.54 d。持续时间更长的抗疫假期会对疫情防控产生更大的影响。为期21 d的全国性抗疫假期可使确诊感染100 000例的时间延迟近10 d。此外，研究发现，在新发突发传染病较早阶段实施抗疫假期比较晚阶段实施对遏制疫情蔓延更有效，抗疫假期期间采取额外的控制措施可以增强疫情控制效果。总之，抗疫假期能够通过有效地减少人群的社交接触频率及范围，从而减缓疫情的传播。抗疫假期使得新冠病毒肺炎传播暂时停滞，为疫情防控争取了时间，科学家可用争取的时间来发现传播途径并确定有效的公共卫生干预措施，政府可用争取的时间来完善基础设施、调配医疗用品、培训和部署专业人力资源，从而为长期防控做好准备。

关键词：新冠病毒肺炎模型春节假期延长保持社交距离

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用于建筑物内COVID-19传播特性研究的元胞模型

Gabriel A. Wainer(其他)

2020年11月28日

关键词：抗击疫情仿真技术人工智能

Indoor massive multiple-input multiple-output channel characterization and performance evaluation Article

Jian-zhi LI, Bo AI, Rui-si HE, Qi WANG, Mi YANG, Bei ZHANG, Ke GUAN, Dan-ping HE, Zhang-dui ZHONG, Ting ZHOU, Nan LI

《信息与电子工程前沿（英文）》 2017年第18卷第6期页码 773-787 doi: 10.1631/FITEE.1700021

摘要：介绍了室内环境下的大规模天线阵列信道测量，天线阵列形式包括64阵元虚拟线阵、64阵元虚拟面阵以及128阵元虚拟面阵。3种不同形式的阵列结构通过三维机械转台构造得到。测量频点包括2、4、6、11、15以及22 GHz，测量带宽为200 MHz。测量同时考虑了直射径场景和非直射径场景。对实测数据进行了基本信道参数萃取，参数包括路径损耗、阴影衰落、功率时延谱和均方根时延扩展。同时给出了上述信道参数的频率依赖性分析，以及阴影衰落与均方根时延扩展的相关性分析。利用实测数据，对基于匹配滤波器的码间干扰消除性能进行了评估，给出了其他信道性能指标如信道香农容量、信道状态数以及信道富裕度的分析结果。分析结果表明：对于具有丰富反散射体的室内环境，即使在直射径存在的情况下，实际大规模天线阵列信道的性能可以接近于独立同分布瑞利信道。

关键词：大规模天线阵列；信道建模；5G；阴影衰落；时延扩展；匹配滤波器；香农容量；信道状态数；信道富裕度

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