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A distributed spatial computing prototype system in grid environment

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Science China(Technological Sciences) 2010年第S1期53卷 25-32页

作者： WU Lun,YAN menglong,GAO Yong,yang ZhenZhen,ZHAO Yong & CHEN Bin Institute of Remote Sensing and Geographic Information System,Peking University,Beijing 100871,China Institute of Remote Sensing and Geographic Information System Peking University Beijing China

Digital Earth has been a hot topic and research trend since it was proposed,and Digital China has drawn much attention in *** a key technique to implement Digital China,grid is an excellent and promising concept to construct a dynamic,inter-domain and distributed computing *** is appropriate to process geographic information across dispersed computing resources in networks effectively and cooperatively.A distributed spatial computing prototype system is designed and implemented with the Globus *** important aspects are discussed in *** architecture is proposed according to the characteristics of grid firstly,and then the spatial resource query and access interfaces are designed for heterogeneous data *** open-up hierarchical architecture for resource discovery and management is represented to detect spatial and computing resources in grid.A standard spatial job management mechanism is implemented by grid service for convenient *** addition,the control mechanism of spatial datasets access is developed based on *** prototype system utilizes the Globus Toolkit to implement a common distributed spatial computing framework,and it reveals the spatial computing ability of grid to support Digital China.

关键词： distributed geographic information processing grid computing Digital China GIS

Coupling Coordination Analysis of Cropland Intensification and Agroecosystem Services:Evidence from Loess Plateau in Shaanxi Province,China

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Chinese Geographical Science 2024年第3期34卷 401-419页

作者： FU Shaowu FU Mengyu QIU menglong Center for Land Resource Research in Northwest China Shaanxi Normal UniversityXi’an 710119China

One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem *** many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely *** view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this *** analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling *** show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to *** service lag was identified as the dominant unbalanced development *** the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess *** coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious ***,cropland intensification practices in the area should be optimized to enhance this coordination *** upward trend was also observed in the coupling coordination degree from2000 to *** withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern *** 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern *** clustering characteristics are mainly attributed to the environmental

关键词： cropland intensification agroecosystem services balance analysis coupling coordination degree Loess Plateau,China

Analysis on influencing factors of detecting chemical oxygen demand in water by three-dimensional spectroscopy

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Optoelectronics Letters 2024年第1期20卷 42-47页

作者： ZHOU Kunpeng LIU Zhiyang CONG menglong MAN Shanxin Inner Mongolia Autonomous Region Joint Laboratory of Nuclear and Radiation Detection College of Physics and Electronic InformationInner Mongolia Minzu UniversityTongliao 028000China College of Information Engineering Jingzhou UniversityJingzhou 434000China Alxa League Meteorological Bureau Alxa 750300China

This paper focuses on the standard chemical oxygen demand(COD)liquid and studies the impact of pH,nitrite nitrogen,nitrate nitrogen,heavy metals,salinity,and other factors on fluorescence intensity and fluorescence peak positions during the detection of COD in water using fluorescence *** influence mechanisms of different environmental factors on fluorescence spectra are also *** indicate that pH value affects the fluorescence emission wavelength(Em),resulting in a red shift from 1.5 to 7.2,and a blue shift from 7.2 to *** nitrogen can react with organic matter in water to form nitro compounds,leading to a decrease in fluorescence *** has a negligible effect on T1 peak but a relatively large effect on T2 *** metal ion concentration has a significant impact on T2 peak,while T1 peak position shifts with an increase in heavy metal *** study aims to explore the factors that can impact the detection of COD in water using three-dimensional fluorescence spectrometry,providing references to improve accuracy and practicability for COD detection based on three-dimensional fluorescence spectrometry.

关键词： chemical negligible nitrate

Dielectric response of ANb_(2)O_(6)(A = Zn, Co, Mn, Ni) columbite niobates: From microwave to terahertz

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Journal of Advanced Ceramics 2024年第8期13卷 1189-1197页

作者： Weijia Luo Shun Wang Siyong Zheng Jining Li menglong Wang Yongzheng Wen ingxia Li Ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Institute of Laser and Optoelectronics School of Precision Instrument and Opto-Electronics EngineeringTianjin UniversityTianjin 300072China Shandong Inspur Artificial Intelligence Research Institute Co. Ltd.Jinan 250013China School of Microelectronics Tianjin UniversityTianjin 300072China

In the upcoming 6-generation(6G)revolution,the achievement of low power consumption has become a key objective in research concerning terahertz *** an important component of passive devices,there are very few low-loss dielectric ceramics in the terahertz *** elucidate the mechanism of loss and promote the application of microwave dielectric ceramics for future 6G technology(covering microwave and terahertz frequencies),the terahertz responses of ANb_(2)O_(6)(A=Zn,Co,Mn,and Ni)columbite niobates were *** influences of magnetic loss on the Qxf values in the microwave range with different transition metal ions in the A-site were reasonably ***,due to the weakened magnetic relaxation properties in the terahertz range,the samples all exhibited low loss and approximate transparency,especially for MnNb_(2)O_(6) and NiNb_(2)O_(6)(tano<0.01 and absorption coefficient<10 cm^(-1) below 1.2 THz),which subverted the definition of traditional low-loss microwave dielectric ***,based on Mie theory,we designed a prototypical broadband metamaterial reflector to validate the applicability of the ANb_(2)O_(6) system in the terahertz band,which is highly important for the development of terahertz ceramic-based passive devices.

关键词： columbite niobates terahertz response transition metal ions magnetic loss ceramic-based metamaterials

基于价值网络的业务外包中介机构运作模式研究

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科技管理研究 2011年第3期31卷 219-223,218页

作者：田耕杨梦龙西安职业技术学院陕西西安710077 焦作高等师范专科学校河南焦作454003

从企业在进行外包过程中面临的风险问题入手,提出建立业务外包中介机构的必要性,并在对业务外包中介机构科学界定的基础上,从价值网的视角对其运作模式进行研究。

关键词：外包风险价值网业务外包中介机构运作模式

Ecological filter walls for efficient pollutant removal from urban surface water

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Environmental Science and Ecotechnology 2024年第5期21卷 230-237页

作者： menglong Liao Ye Qiu Yan Tian Zeng Li Tongtong liu Xinlei Feng Guohong Liu Yujie Feng State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin150090China Heilongjiang Academy of Chemical Engineering No 3Nanhu StreetCentury DistrictHigh-Tech ZoneHarbin150028China

Urban surface water pollution poses significant threats to aquatic ecosystems and human *** nitrogen removal technologies used in urban surface water exhibit drawbacks such as high consumption of carbon sources,high sludge production,and focus on dissolved oxygen(DO)concentration while neglecting the impact of DO ***,we show an ecological filter walls(EFW)that removes pollutants from urban surface *** utilized a polymer-based three-dimensional matrix to enhance water permeability,and emergent plants were integrated into the EFW to facilitate biofilm *** observed that varying aeration intensities within the EFW's aerobic zone resulted in distinct DO gradients,with an optimal DO control at 3.19±0.2 mg L^(-1) achieving superior nitrogen removal ***,the removal efficiencies of total organic carbon,total nitrogen,ammonia,and nitrate were 79.4%,81.3%,99.6%,and 79.1%,*** community analysis under a 3 mg L^(-1) DO condition revealed a shift in microbial composition and abundance,with genera such as Dechloromonas,Acinetobacter,unclassified_f__Comamonadaceae,SM1A02 and Pseudomonas playing pivotal roles in carbon and nitrogen ***,the EFW facilitated shortcut nitrification-denitrification processes,predominantly contributing to nitrogen *** low manufacturing cost,flexible application,small artificial trace,and good pollutant removal ability,EFW has promising potential as an innovative approach to urban surface water treatment.

关键词： Urban water remediation Ecological filter walls Shortcut nitrification-denitrification Dissolved oxygen gradient Nitrogen removal

Plant natural products as effective options for inhibiting foodborne pathogens: A comprehensive review of their activities， mechanisms， and applications in food preservation

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Food Science and Human Wellness 2024年

作者： menglong Liu Haiyan Ding Yu Cao Lijing Liu Qiaoli Xue Yongjin Hu College of Food Science and Technology， Yunnan Agricultural University School of Public Health， Dali University Editorial Department of Journal of Yunnan Agricultural University

In order to ensure food safety， controlling foodborne pathogen contamination is of utmost importance. Growing apprehensions regarding the safety of synthetic antimicrobials， due to their adverse health effects， have prompted a search for alternative options. Plant natural products (PNPs) with antimicrobial activity are being explored as a viable alternative. Among the various antimicrobial natural products studied， plant essential oils， plant flavonoids， plant polyphenols， plant polysaccharides， and plant antimicrobial peptides have been identified as potential candidates. PNPs demonstrate a diverse array of antimicrobial mechanisms， encompassing cell wall and membrane damage， interference with genetic replication， disruption of energy metabolism， and induction of oxidative stress at the single-cell level， as well as inhibition of biofilm formation and quorum sensing at the population level. Certain PNPs have been harnessed as natural antimicrobial agents for the food preservation. The utilization of encapsulation technology proves to be an effective strategy in protecting PNPs， thereby ensuring good antimicrobial efficacy， enhanced dispersibility， and controlled release within food products. The utilization of nanoemulsions， nanoliposomes， edible packaging， electrospun nanofibers， and microcapsules formed by encapsulation has enriched the ways in which PNPs can be applied in food preservation. Although PNPs have great potential in food preservation， their widespread application in the food industry is currently constrained by factors such as production costs， safety concerns， and legal considerations. Chemical synthesis and biosynthesis pathways offer viable strategies for reducing the cost of producing PNPs， and ongoing efforts to assess safety and improve regulatory frameworks are likely to facilitate the broader adoption of PNPs in food preservation practices. This article provides an overview of the main types of PNPs with antimicrobial activity and their prope

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5-Aminolaevulinic acid-based photodynamic therapy for actinic keratosis in Chinese patients: A prospective multicenter study

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Chinese Medical Journal 2024年第12期137卷 1510-1512页

作者： menglong Ran Wenyu Wu yang Tang Liang Zhang Miaojian Wan Siliang Xue Jianglin Zhang Hang Li Department of Dermatology and Venerology Peking University First HospitalNational Clinical Research Center for Skin and Immune DiseasesBeijing Key Laboratory of Molecular Diagnosis on DermatosesBeijing 100034China Department of Dermatology Huashan HospitalFudan UniversityShanghai 200040China The First Affiliated Hospital of Kunming Medical University KunmingYunnan 650032China Department of Dermatology Wuhan No.1 HospitalWuhanHubei 430022China Department of Dermatology The 3rd Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510630China Department of Dermatology Sichuan University West China HospitalChengduSichuan 610044China Shenzhen People’s Hospital(The Second Clinical Medical College Jinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)ShenzhenGuangdong 518020China

To the Editor:Actinic keratosis(AK)is a precancerous skin condition caused by chronic exposure to ultraviolet *** mainly occurs on sun-exposed areas like the head and face,leading to cosmetic concerns and an increased risk of progressing to primary squamous cell carcinoma(with a 0.60%risk at 1 year and 2.57%risk at 4 years).[1]Photodynamic therapy(PDT)is a targeted,non-invasive therapy that has been approved in Europe for the treatment of AK,squamous cell carcinoma in situ,and basal cell carcinomas.5-Aminolaevulinic acid(ALA)-based PDT,which utilizes the photosensitizer ALA,has shown high cure rates,low recurrence rates,and favorable cosmetic outcomes as arst-line treatment for AK.[1]However,due to variations in skin color,ethnicity,and lifestyle habits,the incidence of AK is lower among Asians compared to Caucasians.[1]There are limited clinical studies on PDT for AK in Asia—particularly lacking large-scale multicenter *** knowledge gap hinders the establishment of treatment standards specically tailored for Asian patients with AK undergoing ***,as the aging population increases in Asia,the incidence of AK demand for medical intervention among Asians is also rising *** conducted this multicenter study aiming to comprehensively investigate the efcacy and safety of ALA-PDT in Chinese patients with AK.

关键词： patients treatment utilize

Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang College of Art and Design Harbin UniversityHarbin 150076People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods