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Development of a net ozone production rate detection system based on dual-channel cavity ring-down spectroscopy

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Journal of Environmental Sciences 2025年第3期149卷 419-430页

作者： Jinzhao Tong Renzhi Hu Changjin Hu Xiaoyan Liu Haotian Cai Chuan Lin Liujun Zhong JiaweiWang Pinhua Xie School of Environmental Science and Optoelectronic technology University of Science and Technology of ChinaHefei 230026China Anhui institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Pharmacy Anhui Medical UniversityHefei 230032China

A novel system for measuring net photochemical ozone production rates in the atmosphere based on cavity ring-down spectroscopy(OPR-CRDS)was *** system consists of two chambers(a reaction chamber and a reference chamber)and a dual-channel O_(x)-CRDS *** minimize the wall loss of O_(x)in the chambers,the inner surfaces of both chambers are coated with Teflon *** performance of the OPR-CRDS system was *** was found that even though the photolysis frequency(J value)decreased by 10%,the decrease in the P(O_(3))caused by the ultraviolet-blocking film coating was less than 3%.The two chambers had a good consistency in the mean residence time and the measurement of NO_(2)and O_(x)under the condition of no *** detection limit of the OPR-CRDS was determined to be 0.20 ppbv/*** further verify the accuracy of the system,the direct measurement values of the OPR-CRDS systemwere comparedwith the calculation results based on radical(OH,HO_(2),and RO_(2))reactions,and a good correlation was obtained between the measured and calculated ***,the developed instrument was applied to obtain the comprehensive field observations at an urban site in the Yangtze River Delta(China)for 40 days,the time series and change characteristics of the P(O_(3))were obtained directly,and the good environmental adaptability and stability of the OPR-CRDS system were *** is expected that the new instrument will be beneficial to investigations of the relationship between P(O_(3))and its precursors.

关键词： Ozone Net photochemical production rate CRDS Atmospheric chemistry

Loop Peeling Based on Quasi-Invariance/Induction Variables

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 362-367页

作者： Litong Song, Robert Glück, Yoshihiko Futamura institute for software production technology, Waseda University, Okubo 3 4 1, Shinjuku ku Tokyo 169 8555, Japan institute for software production technology Waseda University Tokyo Japan

Loop optimization plays an important role in compiler optimization and program transformation. Many sophisticated techniques such as loop invariance code motion have been developed. Loop peeling is a technique to assist parallelization of loops by unfolding loops a few times. This paper introduces a novel technique called loop peeling based on quasi invariance/induction variables. It aims at finding a general and automatic method to derive how many times a given loop should be peeled. Our technique allows for a number of iterations before some variables assigned inside a given loop become invariance or induction variables. In this paper we define the notion of quasi invariance/induction variables, present an algorithm for statically computing the optimal peeling length of a given loop. Our technique can increase the accuracy of program analyses, improve the effectiveness of loop peeling and is well suited as supporting other optimization techniques in the context of supercomputers.

关键词： loop peeling parallelization induction variables quasi induction variables quasi invariance variables

维普期刊数据库

A New Encryption Mechanism Supporting the Update of Encrypted Data for Secure and Efficient Collaboration in the Cloud Environment

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 813-834页

作者： Chanhyeong Cho Byeori Kim Haehyun Cho Taek-Young Youn Department of Cyber Security Dankook UniversityYongin16890Republic of Korea Department of software Soongsil UniversitySeoul07027Republic of Korea

With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly ***,traditional collaboration tools primarily rely on access control,leaving data stored on cloud servers vulnerable due to insufficient *** paper introduces a novel mechanism that encrypts data in‘bundle’units,designed to meet the dual requirements of efficiency and security for frequently updated collaborative *** bundle includes updated information,allowing only the updated portions to be reencrypted when changes *** encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes,such as Cipher Block Chaining(CBC)and Counter(CTR),which require decrypting and re-encrypting the entire dataset whenever updates *** proposed method leverages update-specific information embedded within data bundles and metadata that maps the relationship between these bundles and the plaintext *** utilizing this information,the method accurately identifies the modified portions and applies algorithms to selectively re-encrypt only those *** approach significantly enhances the efficiency of data updates while maintaining high performance,particularly in large-scale data *** validate this approach,we conducted experiments measuring execution time as both the size of the modified data and the total dataset size *** show that the proposed method significantly outperforms CBC and CTR modes in execution speed,with greater performance gains as data size ***,our security evaluation confirms that this method provides robust protection against both passive and active attacks.

关键词： Cloud collaboration mode of operation data update efficiency

SolarDesign:An online photovoltaic device simulation and design platform

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Chinese Physics B 2025年第1期34卷 135-141页

作者： Wei E.I.Sha Xiaoyu Wang Wenchao Chen Yuhao Fu Lijun Zhang Liang Tian Minshen Lin Shudi Jiao Ting Xu Tiange Sun Dongxue Liu College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOEKey Laboratory of Material Simulation Methods&Software of MOESchool of Materials Science and EngineeringJilin UniversityChangchun 130012China ZJU-UIUC institute International CampusZhejiang UniversityHaining 314400China Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Science and technology Research institute China Three Gorges CorporationBeijing 101199China

Solar Design(https://***/)is an online photovoltaic device simulation and design platform that provides engineering modeling analysis for crystalline silicon solar cells,as well as emerging high-efficiency solar cells such as organic,perovskite,and tandem *** platform offers user-updatable libraries of basic photovoltaic materials and devices,device-level multi-physics simulations involving optical–electrical–thermal interactions,and circuit-level compact model simulations based on detailed balance *** internationally advanced numerical methods,the platform accurately,rapidly,and efficiently solves optical absorption,electrical transport,and compact circuit *** achieves multi-level photovoltaic simulation technology from“materials to devices to circuits”with fully independent intellectual property *** to commercial softwares,the platform achieves high accuracy and improves speed by more than an order of ***,it can simulate unique electrical transport processes in emerging solar cells,such as quantum tunneling,exciton dissociation,and ion migration.

关键词： photovoltaic device simulation silicon solar cells organic and perovskite solar cells multi-physics and circuit simulation

Estimated Ultimate Recovery and Productivity of Deep Shale Gas Horizontal Wells

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Fluid Dynamics & Materials Processing 2025年第1期21卷 221-232页

作者： Haijie Zhang Haifeng Zhao Ming Jiang Junwei Pu Yuanping Luo Weiming Chen Tongtong Luo Zhiqiang Li Xinan Yu Exploration and Development Department Chongqing Shale Gas Exploration and Development Co.Ltd.Chongqing401120China Oil&Gas technology Research institute Changqing Oilfield CompanyXi’an710018China Exploration and Development Research institute Zhejiang Oilfield CompanyHangzhou310023China Geological Exploration and Development Research institute Chuanqing Drilling Engineering Co.Ltd.Chengdu610056China School of Petroleum and Natural Gas Engineering Chongqing University of Science and TechnologyChongqing401331China technology Department Chongqing University of Science and TechnologyChongqing401331China

Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model is proposed to characterize the effect of pressure drop rate on fracture ***,a production prediction model is introduced accounting for a non-uniform hydraulic fracture conductivity *** results reveal that increasing the fracture conductivity leads to a rapid daily production increase in the early ***,above 0.50 D·cm,a further increase in the fracture conductivity has a limited effect on shale gas production *** initial production is lower under pressure-controlled conditions than that under *** extended pressure control durations,the cumulative production initially increases and then *** a fracture conductivity of 0.10 D·cm,the increase in production output under controlled-pressure conditions is~35%.For representative deep shale gas wells(Southern Sichuan,China),if the pressure drop rate under controlled-pressure conditions is reduced from 0.19 to 0.04 MPa/d,the EUR increase for 5 years of pressure-controlled production is 41.0 million,with an increase percentage of~29%.

关键词： Deep shale gas fracture stress sensitivity pressure-controlled production production prediction

Numerical Simulation of Radiation Transport to Improve Microalgae Cultivation in an Air-Lift Photobioreactor

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Journal of Thermal Science 2025年第1期34卷 62-76页

作者： ZHANG Xianbin LI Mingjia HUNG Tzuchen ZHANG Zixun Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Mechanical Engineering Taipei University of TechnologyTaipei 106344China

A comprehensive numerical model is developed to simulate the growth of microalgae under light/dark cycling *** purpose of this study is to predict the growth rate of Chlorella vulgaris cultivated in photobioreactors(PBRs)in order to improve the light conditions for microalgae and enhance the photosynthetic *** fluid dynamics(CFD)is used to simulate its internal hydrodynamic *** Lagrangian method is employed to track the movement of microalgae *** radiative transfer equation(RTE)is used to obtain light intensity *** combination of light radiation field and microalgae cell motions is used to construct the light history and they are integrated into the model of the photosynthetic units(PSU)to calculate the microalgae growth *** numerical results demonstrate that enhanced light/dark cycling frequency with ordered mixing can promote efficient microalgae *** effect of the vortex flow field generated by the baffles in an air-lift PBR is analyzed for increasing microalgae growth *** using the 1:1 baffle spacing,the biomass production of microalgae is increased by 41.8% compared to the original PBR.

关键词： photobioreactor light distribution particle tracking structure optimization

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High-Precision Sub-Seafloor Velocity Building Based on Joint Tomography and Deep Learning on OBS Data in the South China Sea

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Journal of Earth Science 2025年

作者： Guoxin Chen Jun Li Jinxin Chen Rongsen Du Yutao Liu Yuli Qi Chun Feng Li Xingguo Huang Department of Marine Sciences Zhejiang University Hainan institute Zhejiang University Chinese Academy of Sciences Institute of Software National Key Laboratory of Space Integrated Information System College of Instrumentation and Electrical Engineering Jilin University

INTRODUCTION Crustal velocity model is crucial for describing the subsurface composition and structure, and has significant implications in offshore oil and gas exploration and marine geophysical engineering(Xie et al., 2024). Currently, travel time tomography is the most commonly used method for velocity modeling based on ocean bottom seismometer(OBS) data(Zhang et al., 2023; Sambolian et al., 2021).

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Enhancing Security in Distributed Drone-Based Litchi Fruit Recognition and Localization Systems

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Computers, Materials & Continua 2025年第2期82卷 1985-1999页

作者： Liang Mao Yue Li Linlin Wang Jie Li Jiajun Tan Yang Meng Cheng Xiong Guangdong-Hong Kong-Macao Greater Bay Area Artificial Intelligence Application technology Research institute Shenzhen Polytechnic UniversityShenzhen518055China School of Computer Science and software Engineering University of Science and Technology LiaoningAnshan114051China

This paper introduces an advanced and efficient method for distributed drone-based fruit recognition and localization, tailored to satisfy the precision and security requirements of autonomous agricultural operations. Our method incorporates depth information to ensure precise localization and utilizes a streamlined detection network centered on the RepVGG module. This module replaces the traditional C2f module, enhancing detection performance while maintaining speed. To bolster the detection of small, distant fruits in complex settings, we integrate Selective Kernel Attention (SKAttention) and a specialized small-target detection layer. This adaptation allows the system to manage difficult conditions, such as variable lighting and obstructive foliage. To reinforce security, the tasks of recognition and localization are distributed among multiple drones, enhancing resilience against tampering and data manipulation. This distribution also optimizes resource allocation through collaborative processing. The model remains lightweight and is optimized for rapid and accurate detection, which is essential for real-time applications. Our proposed system, validated with a D435 depth camera, achieves a mean Average Precision (mAP) of 0.943 and a frame rate of 169 FPS, which represents a significant improvement over the baseline by 0.039 percentage points and 25 FPS, respectively. Additionally, the average localization error is reduced to 0.82 cm, highlighting the model’s high precision. These enhancements render our system highly effective for secure, autonomous fruit-picking operations, effectively addressing significant performance and cybersecurity challenges in agriculture. This approach establishes a foundation for reliable, efficient, and secure distributed fruit-picking applications, facilitating the advancement of autonomous systems in contemporary agricultural practices.

关键词： Objective detection deep learning machine learning

Analysis on the University-enterprise Collaborative Training Path for Engineering Doctor from the Perspective of Deep Integration—Innovative Synergies in Talent and technology Development

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计算机教育 2025年第03期 138-144页

作者： Peirong Guo Mingjian Song Chunwei Tian Qi Zhu the School of software Northwestern Polytechnical University Yangtze River Delta Research institute the College of Artificial Intelligence Nanjing University of Aeronautics and Astronautics the College of Computer Science and technology Nanjing University of Aeronautics and Astronautics

With the rapid development of China’s economy,the demand for high-end talents in the field of engineering technology is becoming increasingly *** doctors,as an important force in this field,have a direct impact on the progress of national technological innovation and the upgrading of industrial ***,there are still some issues in the university-enterprise collaboration for engineering doctor training in China,such as unclear cooperation mechanisms and responsibility divisions,insufficient corporate participation and enthusiasm,and imperfect evaluation and feedback *** paper aims to explore the university-enterprise collaborative training path of engineering doctors from the perspective of deep integration,analyzing multiple dimensions including training objectives,curriculum design,practical sessions,mentor teams,and evaluation systems,in order to provide reference for the reform and practice of engineering doctor training in China.

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