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自由贸易协定环保条款促进了环境产品出口吗?——基于双重差分模型的实证分析

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中国地质大学学报（社会科学版） 2022年第4期22卷 64-76页

作者：曹翔蔡勇海南大学经济学院海南海口570228

随着全球生态环境问题的日益突出,环保条款已经成为国与国之间自由贸易协定的重要内容。本文基于2002—2017年中国出口到157个贸易伙伴国的环境产品层面数据,构建双重差分模型考察FTA环保条款对环境产品出口的影响、作用机制及异质性影... 详细信息

随着全球生态环境问题的日益突出,环保条款已经成为国与国之间自由贸易协定的重要内容。本文基于2002—2017年中国出口到157个贸易伙伴国的环境产品层面数据,构建双重差分模型考察FTA环保条款对环境产品出口的影响、作用机制及异质性影响。研究发现:(1)FTA环保条款显著促进了中国环境产品出口规模增长;(2)FTA环保条款对中国环境产品出口的贸易转移效应大于贸易创造效应;(3)相较于发达国家和非“一带一路”沿线国家而言,FTA环保条款对中国环境产品出口的促进作用在发展中国家和“一带一路”沿线国家中更加明显;与可再生能源设备、环境保护型产品以及环境友好型产品相比,FTA环保条款对中国环境产品出口的促进作用主要集中在环境监测分析和评价设备这类产品。

关键词：自由贸易协定环保条款环境产品出口双重差分模型

关于应用骨科手术机器人以降低颈椎后路单开门椎管扩大成形术出血量的研究

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颈腰痛杂志 2024年第2期45卷 340-344页

作者：朱文潇崔宏勋孔亮刘永辉程卫东郑振雨曹向阳河南省洛阳正骨医院(河南省骨科医院)脊柱外科河南郑州450018

目的研究在颈椎后路单开门椎管扩大成形术中,应用骨科手术机器人对术中出血量、术后引流量及隐性失血量的影响。方法将2020年8月~2021年2月该院收治的9例多节段脊髓型颈椎病患者作为研究组,在天玑骨科手术机器人辅助定位下行颈椎后路单... 详细信息

目的研究在颈椎后路单开门椎管扩大成形术中,应用骨科手术机器人对术中出血量、术后引流量及隐性失血量的影响。方法将2020年8月~2021年2月该院收治的9例多节段脊髓型颈椎病患者作为研究组,在天玑骨科手术机器人辅助定位下行颈椎后路单开门椎管扩大成形术;将2019年8月至~2020年7月未使用机器人辅助下行颈椎后路单开门椎管扩大成形术的多节段脊髓型颈椎病患者15例为对照组。计算并对比两组患者手术时间、术中出血量、术后总引流量,隐性失血量、总出血量及颈椎JOA评分等指标。结果研究组患者术中出血量、隐性失血量和总出血量分别为(206.89±39.19)mL、(83.11±24.37)mL、(641.78±63.67)mL,均小于对照组的(245.73±40.55)mL、(134.60±30.54)mL、(726.07±80.69)mL,其差异具有统计学意义(P<0.05);两组手术操作时间及术后总引流量对比,无明显差异。两组患者术前JOA评分无明显差异;研究组末次随访JOA评分为(15.33±2.06)分,显著优于对照组的(13.20±2.45)分,差异有统计学意义(P<0.05)。结论应用骨科手术机器人辅助定位行颈椎后路单开门椎管扩大成形术,有利于精准定位椎管边界,快速、准确定位开门位置,利于手术操作,减少术中出血量、隐性失血量和总出血量,促进患者临床症状改善,值得推广应用。

关键词：骨科手术机器人后路单开门手术失血量脊髓型颈椎病

Quantitative phase imaging based on holography:trends and new perspectives

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Light(Science & Applications) 2024年第7期13卷 1235-1277页

作者： Zhengzhong Huang Liangcai cao Department of Precision Instrument Tsinghua UniversityBeijing 100084China

In 1948,Dennis Gabor proposed the concept of holography,providing a pioneering solution to a quantitative description of the optical *** 75 years of development,holographic imaging has become a powerful tool for optical wavefront measurement and quantitative phase *** emergence of this technology has given fresh energy to physics,biology,and materials *** holography(DH)possesses the quantitative advantages of wide-field,non-contact,precise,and dynamic measurement capability for *** has unique capabilities for the propagation of optical fields by measuring light scattering with phase *** offers quantitative visualization of the refractive index and thickness distribution of weak absorption samples,which plays a vital role in the pathophysiology of various diseases and the characterization of various *** provides a possibility to bridge the gap between the imaging and scattering *** propagation of wavefront is described by the complex *** complex-value in the complex-domain is reconstructed from the intensityvalue measurement by camera in the ***,we regard the process of holographic recording and reconstruction as a transformation between complex-domain and real-domain,and discuss the mathematics and physical principles of *** review the DH in underlying principles,technical approaches,and the breadth of *** conclude with emerging challenges and opportunities based on combining holographic imaging with other methodologies that expand the scope and utility of holographic imaging even *** multidisciplinary nature brings technology and application experts together in label-free cell biology,analytical chemistry,clinical sciences,wavefront sensing,and semiconductor production.

关键词： holographic phase precise

Single-beam leaky-wave antenna with wide scanning angle and high scanning rate based on spoof surface plasmon polariton

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Chinese Physics B 2022年第10期31卷 399-405页

作者：蒋欢曹祥玉刘涛吉地辽日李思佳 Information and Navigation College Air Force Engineering UniversityXi’an 710077China Shaanxi Key Laboratory of Artificially-Structured Functional Materials and Devices Air Force Engineering UniversityXi’an 710051China

We propose a single-beam leaky-wave antenna(LWA) with a wide-scanning angle and a high-scanning rate based on spoof surface plasmon polariton(SSPP) in this paper. The SSPP transmission line(TL) is etched with periodically arranged circular patches, which converts the slow-wave mode into the fast-wave region for radiation. The proposed LWA is designed, fabricated, and tested. The simulated results imply that the proposed LWA not only achieves a high radiation efficiency of about 81.4%, and a high scanning rate of 12.12, but also has a large scanning angle of 176° over a narrow operation bandwidth of 8.3-9.6 GHz(for |S_(11)| <-10 dB). In addition, the simulated average gain of the LWA can reach as high as 10.9 d Bi. The measured scanning angle range is 175° in the operation band of 8.2-9.6 GHz, and the measured average gain is 10.6 dBi. The experimental results are consistent with the simulation, validating its performance. An antenna with high radiation efficiency, wide scanning angle range, and high scanning rate has great potential for application in radar and wireless communication systems.

关键词： spoof surface plasmon polariton(SSPP) leaky wave antenna wide scanning angle high scanning rate

Dynamic Setting Method of Assessment Indicators for Power Curves of Renewable Energy Sources Considering Scarcity of Reserve Resources

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao cao Jilai Yu the Department of Electrical Engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

碳排放权交易试点政策是否促进了碳中和技术创新?

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中国人口·资源与环境 2023年第7期33卷 94-104页

作者：曹翔苏馨儿海南大学经济学院海南海口570228

在“双碳”目标下,中国亟须碳中和技术创新提供关键技术支持,旨在通过“看不见的手”激励经济主体自主进行技术创新的碳交易政策,究竟对碳中和技术创新的影响如何?鲜有文献对此问题展开经验性研究。为此,基于2009—2019年城市面板数据,... 详细信息

在“双碳”目标下,中国亟须碳中和技术创新提供关键技术支持,旨在通过“看不见的手”激励经济主体自主进行技术创新的碳交易政策,究竟对碳中和技术创新的影响如何?鲜有文献对此问题展开经验性研究。为此,基于2009—2019年城市面板数据,将2013年以来在部分省份开展的碳排放权交易试点政策视为一项准自然实验,运用双重差分法评估其对碳中和技术创新的政策净效应、长短期效应及其作用机制,并对该政策效应做了进一步分析。研究发现:①碳交易政策显著促进了试点地区的碳中和技术创新,该结论在包括安慰剂检验和工具变量法等方法在内的一系列稳健性检验中依然成立。②该促进作用在政策实施后的短期和长期内均显著存在,且在长期中更大。③该政策效应主要通过增加研发资本投入和增加研发人员投入两种作用机制实现,且这两种机制的促进作用在长期中更强。④相较于中西部地区、多配额配发模式、中低碳价地区以及负碳技术创新而言,该政策效应对东部地区、只采用免费配发的配额配发模式、碳价格较高地区以及非负碳技术创新更加明显。鉴于此,中国应加快培养如碳交易员和碳排放管理师等专业化人才,从而助力实现“双碳”目标;进一步完善全国统一碳市场;加强对碳市场的协调管理,促进各地区均衡发展;加快完善中国碳交易试点配额的分配机制,适当增加配额拍卖比例;使碳价格充分体现减碳成本,更好地发挥其激励作用;在发展主流低碳技术的同时重点攻克负碳技术,推动碳中和技术创新实现重大突破。

关键词：碳交易政策碳中和技术创新双重差分法

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Numerical and experimental studies of hydrodynamic performance of bionic leading-edge tubercle airfoil

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Journal of Hydrodynamics 2019年第6期31卷 1240-1249页

作者： Chun-yu Guo Zuo-tian Zhang Xu-xiang cao Tie-cheng Wu Yu-min Su College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

This paper studies the bionic tubercle airfoils based on the NACA 0020 prototype airfoil,with 7 models derived from different designs of the span-chord ratios and different tubercle types,along with the option of the wave airfoil surface matching the leading-edge *** water experiments are conducted to test the airfoil profile at a Reynolds number of 3×10^5 and an angle of attack of 0°-30°.Data are recorded by a four-component force balance and the resulted lift,drag,and force moment are *** the analysis of the hydrodynamic characteristics and the flow field characteristics,it is shown that the stall of the tubercle airfoils is milder without an evident stalling angle as compared with that of the normal airfoil *** lift coefficient of the optimized airfoil is significantly elevated at the angle where the NACA 0020 airfoil is in the stall *** lift-drag ratio is also markedly improved at the same *** optimal airfoil profile is finally identified and a further optimization plan is proposed based on the comparison results against the CFD numerical simulation.

关键词： Bionic tubercle computational fluid dynamics stall

Bioinspired Closed-loop CPG-based Control of a Robotic Manta for Autonomous Swimming

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Journal of Bionic Engineering 2024年第1期21卷 177-191页

作者： Yiwei Hao Yonghui cao Yingzhuo cao Xiong Mo Qiaogao Huang Lei Gong Guang Pan Yong cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo 315103China Key Laboratory of Unmanned Underwater Vehicle Technology of Ministry of Industry and Information Technology Xi'an 710072China

Fish in nature exhibit a variety of swimming modes such as forward swimming,backward swimming,turning,pitching,etc.,enabling them to swim in complex scenes such as coral *** is still difficult for a robotic fish to swim autonomously in a confined area as a real ***,we develop an untethered robotic manta as an experimental platform,which consists of two flexible pectoral fins and a tail fin,with three infrared sensors installed on the front,left,and right sides of the head to sense the surrounding *** generate multiple swimming modes of the robotic manta and online switching of different modes,we design a closed-loop Central Pattern Generator(CPG)controller based on distance information and use a combination of phase difference and amplitude of the CPG model to achieve stable and rapid adjustment of yaw *** verify the autonomous swimming ability of the robotic manta in complex scenes,we design an experimental scenario with a concave *** experimental results show that the robotic manta can achieve forward swimming,backward swimming,in situ turning within the concave obstacle,and finally exit from the area safely while relying on the perception of external obstacles,which can provide insight into the autonomous exploration of complex scenes by the biomimetic robotic ***,the swimming ability of the robotic manta is verified by field tests.

关键词： Biomimetic robotic manta Central Pattern Generator Closed-loop control Backward swimming

Multi-scenario land use prediction and layout optimization in Nanjing Metropolitan Area based on the PLUS model

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Journal of Geographical Sciences 2024年第7期34卷 1415-1436页

作者： cao Ji cao Weidong cao Yuhong WANG Xuewei ZHANG Yizhen MA Jinji School of Geography and Tourism Anhui Normal UniversityWuhuAnhui241002China School of Ecology and Environment Anhui Normal UniversityWuhuAnhui241002China

The metropolitan area is a crucial spatial element in promoting new urbanization in *** possesses theoretical and empirical value in the determination of the evolutionary patterns and development trends necessary for regional integration and high-quality *** study focused on Nanjing Metropolitan Area,the first national metropolitan area in China,and established three development scenarios by combining ecological–economic spatial conflict(EESC)zones and national key ecological functional *** scenarios simulate the spatial distribution of future land use and land cover change(LUCC)using the development zone planning function of the patch generation land use simulation(PLUS)*** results show that:(1)Between 2000 and 2020,the most prominent characteristics of land use change were largely the massive expansion of built-up land and the significant decline of farmland,while changes in the area of ecological land were less evident.(2)EESC areas experienced significant changes over the past 20 years,but the overall level of conflict was *** land was the main land use type in the lowest-conflict area,while built-up land was the main land use type in the highest-conflict area.(3)From 2030 to 2050,further expansion of built-up areas is expected,with continued decrease of *** regulation of these land use changes can be achieved through different development zone *** economic development scenario had the largest built-up land area,while the ecological protection scenario had the largest farmland *** study simulates the spatial pattern changes in the metropolitan area based on spatial conflict patterns and national main functional area planning process,providing a scientific reference for future spatial planning and management.

关键词： land use change spatial conflict patch-generating simulation land use prediction Nanjing Metropolitan Area