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Endoscopic intramural cystogastrostomy for treatment of peripancreatic fluid collection: A viewpoint from a surgeon 被引量:1
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作者 Chen-Guo Ker 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期610-613,共4页
Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of... Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of pancreatic pseu-docysts of 20 patients in 2008.From a surgeon’s viewpoint,ETGF is a similar procedure to cystogastrostomy in that they both produce a wide outlet orifice for the drainage of fluid and necrotic debris.ETGF can be performed at least 4 wk after the initial onset of acute pancreatitis and it has a high priority over the surgical approach.However,the surgical approach usually has a better success rate because surgical cystogastrostomy has a wider outlet(>6 cm vs 2 cm)than ETGF.However,percutaneous or endoscopic drainage,ETGF,and surgical approach offer various treatment options for peripancreatic fluid collection patients based on their conditions. 展开更多
关键词 Pancreatitis Pancreatic pseudocyst Endoscopic cystogastrostomy Surgical cystogastrostomy Peripancreatic fluid collection Fenestration for pancreatic cyst
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Customized Convolutional Neural Network for Accurate Detection of Deep Fake Images in Video Collections 被引量:1
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作者 Dmitry Gura Bo Dong +1 位作者 Duaa Mehiar Nidal Al Said 《Computers, Materials & Continua》 SCIE EI 2024年第5期1995-2014,共20页
The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method in... The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method involves extracting structured data from video frames using facial landmark detection,which is then used as input to the CNN.The customized Convolutional Neural Network method is the date augmented-based CNN model to generate‘fake data’or‘fake images’.This study was carried out using Python and its libraries.We used 242 films from the dataset gathered by the Deep Fake Detection Challenge,of which 199 were made up and the remaining 53 were real.Ten seconds were allotted for each video.There were 318 videos used in all,199 of which were fake and 119 of which were real.Our proposedmethod achieved a testing accuracy of 91.47%,loss of 0.342,and AUC score of 0.92,outperforming two alternative approaches,CNN and MLP-CNN.Furthermore,our method succeeded in greater accuracy than contemporary models such as XceptionNet,Meso-4,EfficientNet-BO,MesoInception-4,VGG-16,and DST-Net.The novelty of this investigation is the development of a new Convolutional Neural Network(CNN)learning model that can accurately detect deep fake face photos. 展开更多
关键词 Deep fake detection video analysis convolutional neural network machine learning video dataset collection facial landmark prediction accuracy models
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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen collection preference Dominant plant species Environmental range Geographical range Species traits
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Seismic effectiveness evaluation and optimized design of tie up method for securing museum collections
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作者 Wang Meng Yan Yi +3 位作者 Yang Weiguo Liu Pei Ge Jiaqi Ma Botao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期741-763,共23页
To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used ... To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried out.The influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been explored.Based on the results,seismic effectiveness evaluation indexes of the tie up method are proposed.Reasonable suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and intervention.The analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking responses.Increasing the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the lines.Through comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial pretension.For specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended. 展开更多
关键词 tie up method museum collections shaking table test seismic effectiveness optimized design
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Flight Time Minimization of UAV for Cooperative Data Collection in Probabilistic LoS Channel
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作者 Yan Li Shaoyi Xu +1 位作者 Yunpu Wu Dongji Li 《China Communications》 SCIE CSCD 2024年第2期210-226,共17页
This paper investigates the data collection in an unmanned aerial vehicle(UAV)-aided Internet of Things(IoT) network, where a UAV is dispatched to collect data from ground sensors in a practical and accurate probabili... This paper investigates the data collection in an unmanned aerial vehicle(UAV)-aided Internet of Things(IoT) network, where a UAV is dispatched to collect data from ground sensors in a practical and accurate probabilistic line-of-sight(LoS) channel. Especially, access points(APs) are introduced to collect data from some sensors in the unlicensed band to improve data collection efficiency. We formulate a mixed-integer non-convex optimization problem to minimize the UAV flight time by jointly designing the UAV 3D trajectory and sensors’ scheduling, while ensuring the required amount of data can be collected under the limited UAV energy. To solve this nonconvex problem, we recast the objective problem into a tractable form. Then, the problem is further divided into several sub-problems to solve iteratively, and the successive convex approximation(SCA) scheme is applied to solve each non-convex subproblem. Finally,the bisection search is adopted to speed up the searching for the minimum UAV flight time. Simulation results verify that the UAV flight time can be shortened by the proposed method effectively. 展开更多
关键词 data collection flight time probabilistic line-of-sight channel unlicensed band unmanned aerial vehicle
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A research on the effect of plasma spectrum collection device on LIBS spectral intensity
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作者 林晓梅 董艳杰 +5 位作者 林京君 黄玉涛 杨江飞 岳星宇 张倬嘉 段鑫杨 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期121-128,共8页
Only a small amount of spectral information is collected because the collection solid angle of the optical fiber probe and lens is very limited when collecting spectral information.To overcome this limitation,this stu... Only a small amount of spectral information is collected because the collection solid angle of the optical fiber probe and lens is very limited when collecting spectral information.To overcome this limitation,this study presents a novel method for acquiring plasma spectral information from various spatial directions.A parabolic-shaped plasma spectral collection device(PSCD)is employed to effectively collect more spectral information into the spectrometer,thereby enhancing the overall spectral intensity.The research objects in this study were soil samples containing different concentrations of heavy metals Pb,Cr,and Cd.The results indicate that the PSCD significantly enhances the spectral signal,with an enhancement rate of up to 45%.Moreover,the signal-to-noise ratio also increases by as much as 36%.Simultaneously,when compared to the absence of a device,it is found that there is no significant variation in plasma temperature when the PSCD is utilized.This observation eliminates the impact of the spatial effect caused by the PSCD on the spectral intensity.Consequently,a concentrationspectral intensity relationship curve is established under the PSCD.The results revealed that the linear fitting R^(2)for Pb,Cr,and Cd increased by 0.011,0.001,and 0.054,respectively.Additionally,the limit of detection(LOD)decreased by 0.361 ppm,0.901 ppm,and 0.602 ppm,respectively.These findings indicate that the spectral enhancement rate elevates with the increase in heavy metal concentration.Hence,the PSCD can effectively enhance the spectral intensity and reduce the detection limit of heavy metals in soil. 展开更多
关键词 LIBS plasma spectrum collection device spectral enhancement plasma temperature limit of detection
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Actor-Critic-Based UAV-Assisted Data Collection in the Wireless Sensor Network
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作者 Huang Xiaoge Wang Lingzhi +1 位作者 He Yong Chen Qianbin 《China Communications》 SCIE CSCD 2024年第4期163-177,共15页
Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacki... Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacking communication infrastructure.Unmanned aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high mobility.In this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the WSN.Firstly,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial layers.The ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the UAVs.The aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for analysis.Secondly,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of CHs.Moreover,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with CHs.Finally,simulation results verify the effectiveness of the proposed algorithms. 展开更多
关键词 actor critic data collection deep reinforcement learning unmanned aerial vehicle wireless sensor network
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Reliable Data Collection Model and Transmission Framework in Large-Scale Wireless Medical Sensor Networks
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作者 Haosong Gou Gaoyi Zhang +2 位作者 RenêRipardo Calixto Senthil Kumar Jagatheesaperumal Victor Hugo C.de Albuquerque 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1077-1102,共26页
Large-scale wireless sensor networks(WSNs)play a critical role in monitoring dangerous scenarios and responding to medical emergencies.However,the inherent instability and error-prone nature of wireless links present ... Large-scale wireless sensor networks(WSNs)play a critical role in monitoring dangerous scenarios and responding to medical emergencies.However,the inherent instability and error-prone nature of wireless links present significant challenges,necessitating efficient data collection and reliable transmission services.This paper addresses the limitations of existing data transmission and recovery protocols by proposing a systematic end-to-end design tailored for medical event-driven cluster-based large-scale WSNs.The primary goal is to enhance the reliability of data collection and transmission services,ensuring a comprehensive and practical approach.Our approach focuses on refining the hop-count-based routing scheme to achieve fairness in forwarding reliability.Additionally,it emphasizes reliable data collection within clusters and establishes robust data transmission over multiple hops.These systematic improvements are designed to optimize the overall performance of the WSN in real-world scenarios.Simulation results of the proposed protocol validate its exceptional performance compared to other prominent data transmission schemes.The evaluation spans varying sensor densities,wireless channel conditions,and packet transmission rates,showcasing the protocol’s superiority in ensuring reliable and efficient data transfer.Our systematic end-to-end design successfully addresses the challenges posed by the instability of wireless links in large-scaleWSNs.By prioritizing fairness,reliability,and efficiency,the proposed protocol demonstrates its efficacy in enhancing data collection and transmission services,thereby offering a valuable contribution to the field of medical event-drivenWSNs. 展开更多
关键词 Wireless sensor networks reliable data transmission medical emergencies CLUSTER data collection routing scheme
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Advances in Research of Collection and Detection Methods of Microplastics in Environment
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作者 Yunshuang FU Zhen ZHAO +4 位作者 Peng WAN Guoyan WEN Haibo FAN Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2024年第9期23-27,31,共6页
As a new type of environmental pollutants,microplastics have gradually attracted people's attention.A large number of plastics discharged into the environment by human beings are constantly aging and breaking,and ... As a new type of environmental pollutants,microplastics have gradually attracted people's attention.A large number of plastics discharged into the environment by human beings are constantly aging and breaking,and finally become microplastics.Microplastics can adsorb pollutants in the environment,and their components have certain toxicity,which can cause different degrees of harm to organisms.Due to the structural characteristics of microplastic particles,such as small particle size,large specific surface area,and their distribution in different environmental media,it is very difficult to accurately detect microplastics.Reliable collection and detection methods are the key to the study of environmental behavior of microplastics.In this study,the collection and detection methods of microplastics in the environment were reviewed,and the development direction of microplastics detection technology in the future was prospected.This study has a certain reference value for the related research and the prevention and treatment of micro-plastic pollution. 展开更多
关键词 Microplastics collection method Detection method
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Endoscopic ultrasound-guided pancreatic fluid collection drainage: Where are we?
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作者 Anupam Kumar Singh Manish Manrai Rakesh Kochhar 《World Journal of Gastrointestinal Endoscopy》 2024年第6期273-281,共9页
Pancreatic fluid collections(PFCs)result from injury to the pancreas from acute or chronic pancreatitis,surgery,or trauma.Management of these collections has evolved over the last 2 decades.The choice of interventions... Pancreatic fluid collections(PFCs)result from injury to the pancreas from acute or chronic pancreatitis,surgery,or trauma.Management of these collections has evolved over the last 2 decades.The choice of interventions includes percu-taneous,endoscopic,minimally invasive surgery,or a combined approach.Endoscopic drainage is the drainage of PFCs by creating an artificial communication between the collection and gastrointestinal lumen that is maintained by placing a stent across the fistulous tract.In this editorial,we endeavored to update the current status of endoscopic ultrasound-guided drainage of PFCs. 展开更多
关键词 Pancreatic fluid collections Endoscopic ultrasound-guided drainage Endoscopic necrosectomy Lumen apposing metal stent Review
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Early endoscopic management of an infected acute necrotic collection misdiagnosed as a pancreatic pseudocyst: A case report
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作者 Hong-Ying Zhang Chen-Cong He 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期609-615,共7页
BACKGROUND Infected acute necrotic collection(ANC)is a fatal complication of acute pancre-atitis with substantial morbidity and mortality.Drainage plays an exceedingly important role as the first step in invasive inte... BACKGROUND Infected acute necrotic collection(ANC)is a fatal complication of acute pancre-atitis with substantial morbidity and mortality.Drainage plays an exceedingly important role as the first step in invasive intervention for infected necrosis;however,there is great controversy about the optimal drainage time,and better treatment should be explored.CASE SUMMARY We report the case of a 43-year-old man who was admitted to the hospital with severe intake reduction due to early satiety 2 wk after treatment for acute pancre-atitis;conservative treatment was ineffective,and a pancreatic pseudocyst was suspected on contrast-enhanced computed tomography(CT).Endoscopic ultra-sonography(EUS)suggested hyperechoic necrotic tissue within the cyst cavity.The wall was not completely mature,and the culture of the puncture fluid was positive for A-haemolytic Streptococcus.Thus,the final diagnosis of ANC in-fection was made.The necrotic collection was not walled off and contained many solid components;therefore,the patient underwent EUS-guided aspiration and lavage.Two weeks after the collection was completely encapsulated,pancreatic duct stent drainage via endoscopic retrograde cholangiopancreatography(ERCP)was performed,and the patient was subsequently successfully discharged.On repeat CT,the pancreatic cysts had almost disappeared during the 6-month fo-llow-up period after surgery.CONCLUSION Early EUS-guided aspiration and lavage combined with late ERCP catheter drainage may be effective methods for intervention in infected ANCs. 展开更多
关键词 Infected acute necrotic collection Pancreatic pseudocyst Endoscopic ultrasonography Endoscopic retrograde cholangiopancreatography Endoscopic ultrasound-guided fine-needle aspiration Case report
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Association between acute peripancreatic fluid collections and early readmission in acute pancreatitis:A propensity-matched analysis
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作者 Hassam Ali Faisal Inayat +13 位作者 Waqas Rasheed Arslan Afzal Ahtshamullah Chaudhry Pratik Patel Attiq Ur Rehman Muhammad Sajeel Anwar Gul Nawaz Muhammad Sohaib Afzal Amir H Sohail Subanandhini Subramanium Dushyant Singh Dahiya Deepa Budh Babu P Mohan Douglas G Adler 《World Journal of Experimental Medicine》 2024年第2期75-88,共14页
BACKGROUND Patients with acute pancreatitis(AP)frequently experience hospital readmissions,posing a significant burden to healthcare systems.Acute peripancreatic fluid collection(APFC)may negatively impact the clinica... BACKGROUND Patients with acute pancreatitis(AP)frequently experience hospital readmissions,posing a significant burden to healthcare systems.Acute peripancreatic fluid collection(APFC)may negatively impact the clinical course of AP.It could worsen symptoms and potentially lead to additional complications.However,clinical evidence regarding the specific association between APFC and early readmission in AP remains scarce.Understanding the link between APFC and readmission may help improve clinical care for AP patients and reduce healthcare costs.AIM To evaluate the association between APFC and 30-day readmission in patients with AP.METHODS This retrospective cohort study is based on the Nationwide Readmission Database for 2016-2019.Patients with a primary diagnosis of AP were identified.Participants were categorized into those with and without APFC.A 1:1 propensity score matching for age,gender,and Elixhauser comorbidities was performed.The primary outcome was early readmission rates.Secondary outcomes included the incidence of inpatient complications and healthcare utilization.Unadjusted analyses used Mann-Whitney U andχ2 tests,while Cox regression models assessed 30-day readmission risks and reported them as adjusted hazard ratios(aHR).Kaplan-Meier curves and log-rank tests verified readmission risks.RESULTS A total of 673059 patients with the principal diagnosis of AP were included.Of these,5.1%had APFC on initial admission.After propensity score matching,each cohort consisted of 33914 patients.Those with APFC showed a higher incidence of inpatient complications,including septic shock(3.1%vs 1.3%,P<0.001),portal venous thrombosis(4.4%vs 0.8%,P<0.001),and mechanical ventilation(1.8%vs 0.9%,P<0.001).The length of stay(LOS)was longer for APFC patients[4(3-7)vs 3(2-5)days,P<0.001],as were hospital charges($29451 vs$24418,P<0.001).For 30-day readmissions,APFC patients had a higher rate(15.7%vs 6.5%,P<0.001)and a longer median readmission LOS(4 vs 3 days,P<0.001).The APFC group also had higher readmission charges($28282 vs$22865,P<0.001).The presence of APFC increased the risk of readmission twofold(aHR 2.52,95%confidence interval:2.40-2.65,P<0.001).The independent risk factors for 30-day readmission included female gender,Elixhauser Comorbidity Index≥3,chronic pulmonary diseases,chronic renal disease,protein-calorie malnutrition,substance use disorder,depression,portal and splenic venous thrombosis,and certain endoscopic procedures.CONCLUSION Developing APFC during index hospitalization for AP is linked to higher readmission rates,more inpatient complications,longer LOS,and increased healthcare costs.Knowing predictors of readmission can help target high-risk patients,reducing healthcare burdens. 展开更多
关键词 Acute pancreatitis Acute peripancreatic fluid collections Readmission predictors Inpatient complications Healthcare utilization and costs
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Exploring Corporate Tax Compliance in the Era of Digital Tax Collection and Administration:Insights from the“Golden Tax Phase Four”Project
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作者 Kai Fan Yujin Xie +1 位作者 Wenjun Xu Haopeng Wei 《Proceedings of Business and Economic Studies》 2024年第2期151-156,共6页
This article primarily examines the current state of tax collection and management,alongside other associated issues.It integrates insights from China’s“14th Five-Year Plan”and anticipates the imminent implementati... This article primarily examines the current state of tax collection and management,alongside other associated issues.It integrates insights from China’s“14th Five-Year Plan”and anticipates the imminent implementation of the“Golden Tax Phase Four.”With this backdrop,the article offers recommendations for advancing the reform of the tax collection and management system,fostering the development of intelligent taxation,and accelerating the modernization of tax collection and management in China. 展开更多
关键词 Golden Tax Phase Four Modernization of tax collection and administration Tax compliance
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浅议Worldcat Collection Analysis的功能及其应用 被引量:3
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作者 邢洁 《新世纪图书馆》 CSSCI 2011年第4期18-20,共3页
馆藏分析是图书馆采访工作中重要的一环,过去图书馆所使用的馆藏分析工具有较大的局限性。OCLC最新开发的Worldcat Collection Analysis是面向图书情报学界的专业的馆藏分析工具,能够提供对某一图书馆所有馆藏及其使用状态的概览。这种... 馆藏分析是图书馆采访工作中重要的一环,过去图书馆所使用的馆藏分析工具有较大的局限性。OCLC最新开发的Worldcat Collection Analysis是面向图书情报学界的专业的馆藏分析工具,能够提供对某一图书馆所有馆藏及其使用状态的概览。这种馆藏分析所得出的数据能够为采购、数字化项目和剔旧决策提供信息,并为项目评估和认证提供帮助。 展开更多
关键词 馆藏分析 馆藏建设 WORLDCAT collection ANALYSIS
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Genetic Diversity Analysis and Constructing Core Collection Based on Phenotypes in Cotton 被引量:1
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作者 贺道华 邢宏宜 +2 位作者 赵俊兴 李婷婷 赵艳宁 《Agricultural Science & Technology》 CAS 2010年第6期57-60,174,共5页
In that DNA diversity detected nowadays could not mean phenotypic diversity,it is the precondition of breeding project and basic research of crop improvement that genetic diversity analysis and sampling of core collec... In that DNA diversity detected nowadays could not mean phenotypic diversity,it is the precondition of breeding project and basic research of crop improvement that genetic diversity analysis and sampling of core collection by phenotypes.Phenotyping and statistic analysis on 9 traits of 92 accessions of cotton germplasm resource from three species(Gossypium hirsutum L.,Gossypium barbadence L.and Gossypium arboreum L.)were conducted.And the statistics(variation coefficient,proportion of special accessions and Shannon-Weaver information index)indicated that initial collection had abundant phenotypic diversity;software NTSYS-pc and the unweighted pair group method of arithmetic(UPGMA)were used for the cluster analysis on genetic similarity coefficient and genetic distance matrix,and the result showed that the genetic relationship among accessions was highly consistent with the pedigree;22 accessions of core collection were selected by software QGAStation,four statistics,such as variance difference percentage(VD%),mean difference percentage(MD%),coincidence rate(CR%)and variable rate(VR%),showed that the genetic diversity of core collection was approximately equal to the initial collection.The results of genetic diversity analysis based on phenotypic data and sampling of core collection would provide reference for breeding projects and basic research. 展开更多
关键词 COTTON Core collection Fiber quality Genetic diversity Germplasm resource
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Practice and analysis of recycling non-drinking water from air-condition and reverse-osmosis system into rainwater collection system 被引量:2
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作者 王小红 邵煜然 王靖华 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期169-174,共6页
This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilizat... This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilization, and precipitation adjustment.The rainwater collection system in this program also adds the condensation water from the heating, ventilation and air conditioning ( HVAC) system and the concentration from the reverse-osmosis system used for watering greens and supplying waterscapes.By calculating, the quantity of the HVAC condensation water in summer is 3.48 m3/d, and the quantity of the reverse-osmosis concentrated water is 198 to 396 L/d.This method solves the water shortage caused by high evaporation in summer and low precipitation in winter.Supported by empirical monitoring data, the proposed method significantly increases the economic efficiency of the system during the summer period. 展开更多
关键词 rainwater collection heating ventilation and air conditioning condensation water precipitation analysis reverse-osmosis concentrated water
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Information Collection of Land Use Status Based on Large Scale Topographic Map
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作者 何立恒 魏浩翰 鲍其胜 《Journal of Landscape Research》 2010年第12期54-57,111,共5页
With large scale topographic map charted in accordance with Topographic Map Symbols of 1:500 1:1 000 1:2 000(GB/T 20257.1-2007) as the base map of land survey,the land use status information was collected from the map... With large scale topographic map charted in accordance with Topographic Map Symbols of 1:500 1:1 000 1:2 000(GB/T 20257.1-2007) as the base map of land survey,the land use status information was collected from the map based on the standard in Present Status Classification of Land Utilization(GB/T 21010-2007).The study discussed in details the information of some land types including water system,residential sites,facilities,transportation,pipeline,vegetation,soils and so on,and pointed out problems on extracting land use status information from large scale topographic map.In order to share resources and save social costs,it suggested unifying the standard to classify land types and define all kinds of land types by quantitative values. 展开更多
关键词 Topographic MAP LAND USE STATUS INFORMATION collection
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Status Quo of Collection and Utilization of Rice and Wheat Straw in Jiangsu Province and the Countermeasures
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作者 张斯梅 杨四军 +1 位作者 石祖梁 常志州 《Agricultural Science & Technology》 CAS 2015年第9期2014-2019,共6页
A case study of Jiangsu Province was conducted using questionnaires and field survey to explore the status quo of the collection and utilization of rice and wheat straw of the province. Problems in collecting the stra... A case study of Jiangsu Province was conducted using questionnaires and field survey to explore the status quo of the collection and utilization of rice and wheat straw of the province. Problems in collecting the straw were analyzed taking into account meteorological data of the rice and wheat harvesting seasons in the region. Results show:(1) Currently, the main handling way of rice and wheat straw was directly returning to field. The peasant households of straw returning from investigated townships A and B respectively occupied 22.01% and 28.75% of investigation households, and both of the two townships had a considerable portion of the straw wasted or improperly disposed. In township B, over 50% of the farmer households surveyed failed to make sure of any of the straw, and as high as over55% of the straw was discarded or burnt.(2) During the rice and wheat harvesting seasons, the ten-day precipitation was among 7.21-87.28 mm, and the ten-day precipitation days were among 1.53-5.00 d. Such weather not only affected timely harvesting of rice and wheat, but also seriously impeded baling, transportation and storage of straw.(3) As the crops must be harvested in a relatively short and concentrated time period, large volumes of straw were turned out within a few days.Moreover, harvesting of the first crop often coincided with sowing, leaving little time available for straw collection.(4) Straw collection was very low in economic benefit.A farmer can only get 60-90 RMB per day from straw collection and transportation,which was much lower than what they can get by working as migrant workers in the city.(5) Machines designed for straw collection were rare and those now used in the operation were low in efficiency and needed to be improved technically,which directly affected the efficiency of straw collection. The above-listed findings indicates that time shortage, negative weather condition, low benefit and low mechanization level were major factors affecting straw collection. To solve the problems,the following proposals were brought forth, that is, improving the economic benefit of straw collection as a driving force, accelerating the research and development of rice and wheat sheaf-binding reaping machine, and setting up a long-term operational mechanism for straw recovery, in the hope that this study may provide some useful ideas to help solve the problems. 展开更多
关键词 Rice and wheat straw collection MECHANIZATION BENEFIT
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基于“Zcollection”的资源集合元数据标准体系研究 被引量:4
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作者 赵军 宋扬 王先来 《制造业自动化》 北大核心 2005年第2期70-71,78,共3页
分析了 Zcollection 的特点及其对资源集合、对象和资源相互之间关系的描述;对基于 Zcollection的资源集合元数据标准体系进行了探讨,并指出该体系建设中需要注意的关键问题。
关键词 Zcollection 资源集合 元数据标准体系
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Using 3D TCAD Simulation to Study Charge Collection of a p-n Junction in a 0.18μm Bulk Process
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作者 梁斌 陈书明 刘必慰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1692-1697,共6页
Single event transient of a real p-n junction in a 0.18μm bulk process is studied by 3D TCAD simulation. The impact of voltage, temperature, substrate concentration, and LET on SET is studied. Our simulation results ... Single event transient of a real p-n junction in a 0.18μm bulk process is studied by 3D TCAD simulation. The impact of voltage, temperature, substrate concentration, and LET on SET is studied. Our simulation results demonstrate that biases in the range 1.62 to 1.98V influence DSET current shape greatly and total collected charge weakly. Peak current and charge collection within 2ns decreases as temperature increases,and temperature has a stronger influence on SET currents than on total charge. Typical variation of substrate concentration in modern VDSM processes has a negligible effect on SEEs. Both peak current and total collection charge increases as LET increases. 展开更多
关键词 charge collection p-n junction very deep sub-micro 3D device simulation RADIATION
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