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Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test
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作者 Wu Houli Guo Endong +2 位作者 Wang Jingyi Dai Xin Dai Chenxi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期163-178,共16页
As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scal... As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame structure.Different material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic performance.Floor response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical simulation.The acceleration response and displacement response of different combinations are compared.The results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes. 展开更多
关键词 water supply pipe different materials shaking table test amplification factor seismic fragility
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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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作者 Yasmin Alaa Hassan Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2024年第1期1423-1442,共20页
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))... Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness. 展开更多
关键词 Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding
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Accelerated generation of holograms with ultra-low memory symmetrically high-compressed look-up table
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作者 杨燕 朱建英 +1 位作者 孙敏远 毕勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期466-471,共6页
Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents... Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents a hologram generation method,i.e.,a symmetrically high-compressed look-up table method,which can reduce memory usage by50%.In offline computing,half of the basic horizontal and vertical modulation factors are stored,halving the memory requirements without affecting inline speed.Currently,its potential extends to various holographic applications,including the production of optical diffraction elements. 展开更多
关键词 computergenerated hologram look-up table HOLOGRAPHY
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A novel control strategy for reproducing the floor motions of high-rise buildings by earthquake-simulating shake tables
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作者 Yuteng Cao Zhe Qu Xiaodong Ji 《Earthquake Research Advances》 CSCD 2024年第1期67-75,共9页
To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Tab... To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Table(NEST)has been developed.The testbed consists of three consecutive floors of steel structure.The bottom two floors provide a space to accommodate a full-scale room.To fully explore the flexibility of NEST,we propose a novel control strategy to generate the required shake table input time histories for the testbed to track the target floor motions of the buildings of interest with high accuracy.The control strategy contains two parts:an inverse dynamic compensation via simulation of feedback control systems(IDCS)algorithm and an offline iteration procedure based on a refined nonlinear numerical model of the testbed.The key aspects of the control strategy were introduced in this paper.Experimental tests were conducted to simulate the seismic responses of a full-scale office room on the 21^(st)floor of a 42-story high-rise building.The test results show that the proposed control strategy can reproduce the target floor motions of the building of interest with less than 20%errors within the specified frequency range. 展开更多
关键词 Shake table test Nonstructural element High-rise building Open-loop IDCS algorithm Off-line iteration
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Impact of water table on hierarchically nested groundwater flow system
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作者 Jun Zhang Rong-zhe Hou +2 位作者 Kun Yu Jia-qiu Dong Li-he Yin 《Journal of Groundwater Science and Engineering》 2024年第2期119-131,共13页
Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flo... Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems.Moreover,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale.Based on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and climate.Two criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow pattern.Then,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion.The applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow systems.The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns. 展开更多
关键词 Water table configuration Groundwater flow pattern Analytical models Top boundary condi-tions Ordos Plateau
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Opinions of Students on the Contribution of the DIVA 3D Virtual Dissection Table to the Teaching of Anatomy at the Faculty of Medicine and Odontostomatology of Bamako
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作者 Abdoulaye Kanté Tata Touré +8 位作者 Ousmane Toumany Chérif Haidara Uhl Jean François Mariam Daou Mamadou A. Keita Bakary Keïta Bréhima Bengaly Drissa Traoré Adégné Togo Nouhoum Ongoïba 《Forensic Medicine and Anatomy Research》 2024年第2期13-25,共13页
Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from Nov... Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from November 1 to December 30, 2023 at the clinical and morphological anatomy laboratory of the Faculty of Medicine and Odontostomatology of Bamako. Included in this study were students who participated in practical and tutorial sessions. The variables studied during this study were: the previous performance of dissection on a cadaver by the students, the opinion of the students on dissection on a cadaver, the replacement of dissection on a cadaver by virtual dissection in the absence of a body, the level student satisfaction. Results: We surveyed 130 participants. The average age was 22 ± 0.2 years with extremes of 17 and 29 years. 95.3% of participants were students. According to 66.7% of participants, virtual dissection is a good palliative in the absence of a corpse. 95.3% of participants found using the virtual dissection table easy with an average of 7.88 ± 1.4. The overall assessment was well rated by 99.3% of participants. Conclusion: According to the results of this study, the virtual dissection table should be improved by integrating commented videos. The use of the DIVA 3D virtual dissection table during practical and tutorial sessions is well appreciated by the students. We believe that the teaching of anatomy using 3D digital technology should be included in the study programs of the Faculty of Medicine and Odontostomatology. 展开更多
关键词 Student Opinion CONTRIBUTION DIVA 3D Virtual Dissection table Anatomy Teaching FMOS
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The Periodic Table of Primes
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作者 Han-Lin Li Shu-Cherng Fang Way Kuo 《Advances in Pure Mathematics》 2024年第5期394-419,共26页
Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers... Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers out of a period 2×3×5×7=210 to be the roots of all primes as well as composites without factors of 2, 3, 5, and 7. Each prime, twin primes, or composite without factors of 2, 3, 5, and 7 is an offspring of the 48 integers uniquely allocated on the PTP. Three major establishments made in the article are the Formula of Primes, the Periodic Table of Primes, and the Counting Functions of Primes and Twin Primes. 展开更多
关键词 PRIMES COMPOSITES the Periodic table of Primes
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THE CONSTRUCTION OF SOME FORESTRY TABLES FOR DAHURIAN LARCH PLANTATIONS 被引量:1
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作者 李长胜 陈祥伟 刘亚范 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第2期5-8,共4页
Several growth models were selected to fit data of dahurian larch plantations using nonlinear regression analysis. The best models were used to construct the site index table' the 2-way volume table and the growth... Several growth models were selected to fit data of dahurian larch plantations using nonlinear regression analysis. The best models were used to construct the site index table' the 2-way volume table and the growth process table. The Chapman-Richards equation is the best model used as the guide curve to form the site index table for dahurian larch plantations. 展开更多
关键词 Forestry table Site index table 2-way volume table Growth process table Dahurian larch PLANTATION
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Determination method of permafrost table in seasonal frozen soil areas under“Water-Heat-Salt”coupling
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作者 WANG Fang YANG Zhong +1 位作者 LIU Kai LU Chang-long 《Journal of Mountain Science》 SCIE CSCD 2023年第11期3266-3282,共17页
The permafrost table is an important index for the design and construction of roads in cold regions,so it is necessary to find a convenient,accurate and fast judgment method to determine the permafrost table.In this s... The permafrost table is an important index for the design and construction of roads in cold regions,so it is necessary to find a convenient,accurate and fast judgment method to determine the permafrost table.In this study,a three-field coupled model was established based on the hydrothermal salt coupling within the permafrost and the similarity theory,and the changes of the permafrost table under different temperature,moisture and salt conditions were numerically simulated by considering the transient temperature change and the influence of the permafrost layer on the seasonally thawed layer.In addition,an accelerated permafrost table test method was designed based on the time-domain variation and hydrothermal salt coupling by the similarity theory,which rapidly simulated the permafrost table change under different temperatures,moisture,and salts in the natural environment.Comparing the simulation and test results with the measured values in the field,the errors are less than 3%,which verified the feasibility of the method for determining the permafrost table,and the simulated results are better than the test results.Results show that the results of determining the permafrost table with a single index have different degrees of deviation,and the permafrost table obtained by the temperature index is the most accurate in general,and it is more accurate to use the average value of the three indexes as the permafrost table compared with a single index. 展开更多
关键词 Permafrost table Hydrothermal salt coupling Seasonally thawed layer Numerical simulation Accelerated test
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Shaking table test and cumulative deformation evaluation analysis of a tunnel across the hauling sliding surface
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作者 Lifang Pai Honggang Wu Xu Wang 《Deep Underground Science and Engineering》 2023年第4期371-393,共23页
To explore the cumulative deformation effect of the dynamic response of a tunnel crossing the hauling sliding surface under earthquakes,the shaking table test was conducted in this study.Combined with the numerical ca... To explore the cumulative deformation effect of the dynamic response of a tunnel crossing the hauling sliding surface under earthquakes,the shaking table test was conducted in this study.Combined with the numerical calculations,this study proposed magnification of the Arias intensity(MIa)to characterize the overall local deformation damage of the tunnel lining in terms of the deformation characteristics,frequency domain,and energy.Using the time‐domain analysis method,the plastic effect coefficient(PEC)was proposed to characterize the degree of plastic deformation,and the applicability of the seismic cumulative failure effect(SCFE)was discussed.The results show that the low‐frequency component(f1 and f2≤10 Hz)and the high‐frequency component(f3 and f4>10 Hz)acceleration mainly cause global and local deformation of the tunnel lining.The local deformation caused by the high‐frequency wave has an important effect on the seismic damage of the lining.The physical meaning of PEC is more clearly defined than that of the residual strain,and the SCFE of the tunnel lining can also be defined.The SCFE of the tunnel lining includes the elastic deformation effect stage(<0.15g),the elastic–plastic deformation effect stage(0.15g–0.30g),and the plastic deformation effect stage(0.30g–0.40g).This study can provide valuable theoretical and technical support for the construction of traffic tunnels in high‐intensity earthquake areas. 展开更多
关键词 magnification of Arias intensity plastic effect coefficient seismic action seismic cumulative failure effect shaking table test tunnel engineering
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Hash Table Assisted Efficient File Level De-Duplication Scheme in SD-IoV Assisted Sensing Devices
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作者 Ghawar Said Ata Ullah +4 位作者 Anwar Ghani Muhammad Azeem Khalid Yahya Muhammad Bilal Sayed Chhattan Shah 《Intelligent Automation & Soft Computing》 2023年第10期83-99,共17页
The Internet of Things(IoT)and cloud technologies have encouraged massive data storage at central repositories.Software-defined networks(SDN)support the processing of data and restrict the transmission of duplicate va... The Internet of Things(IoT)and cloud technologies have encouraged massive data storage at central repositories.Software-defined networks(SDN)support the processing of data and restrict the transmission of duplicate values.It is necessary to use a data de-duplication mechanism to reduce communication costs and storage overhead.Existing State of the art schemes suffer from computational overhead due to deterministic or random tree-based tags generation which further increases as the file size grows.This paper presents an efficient file-level de-duplication scheme(EFDS)where the cost of creating tags is reduced by employing a hash table with key-value pair for each block of the file.Further,an algorithm for hash table-based duplicate block identification and storage(HDBIS)is presented based on fingerprints that maintain a linked list of similar duplicate blocks on the same index.Hash tables normally have a consistent time complexity for lookup,generating,and deleting stored data regardless of the input size.The experiential results show that the proposed EFDS scheme performs better compared to its counterparts. 展开更多
关键词 Hash table de-duplication linked list IoT sensing devices
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Seasonal Effect on Weather Elements on Water Table Fluctuation in Potable Wells in Kono District, Eastern Sierra Leone
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作者 Richard Tamba Simbo Alhaji Brima Gogra +1 位作者 Yahaya Kudus Kawa Paul Juana Moiwo 《Open Journal of Applied Sciences》 2023年第11期2198-2209,共12页
The study investigated the seasonal effects of weather elements on water table fluctuations in drinking wells in Nimikoro and Tankoro Chiefdoms in Kono District, Eastern Sierra Leone. The study specifically determined... The study investigated the seasonal effects of weather elements on water table fluctuations in drinking wells in Nimikoro and Tankoro Chiefdoms in Kono District, Eastern Sierra Leone. The study specifically determined the trends in precipitation, air temperature and relative humidity relative to water table depth and water volume in both manually dug and mechanically drilled water wells in the chiefdoms. The key objective was to provide a clear guide on sustainable well development and operation in the study area and beyond. To do so, the depth of each well was taken and the water table measured. Also, data on key weather elements such as precipitation, air temperature and relative humidity were collected on the 15<sup>th</sup> of every month for a period of one year. The data were analyzed on Excel, SPSS and ArcGIS platforms for monthly and seasonal trends in the time-space fabric. The results showed that the depth to water table was high in the dries (small well water volume) and low in the rains (large well water volume) for both manually dug and mechanically drilled wells. Well water temperature increased as temperature increased during the dry season but decreased as temperature decreased during the rainy season. The study showed that weather elements such as precipitation and temperature had direct impact on groundwater availability. This is critical for groundwater development and management in the study area and in Sierra Leone at large. 展开更多
关键词 GROUNDWATER Water table Relative Humidity PRECIPITATION Temperature
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Displaying Water Table Levels, Flow Direction for Predicting Construction Techniques Using Geographic Information: Case Study of Kumba (South West, Cameroon)
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作者 Benjamin Bahel Blaise Bayiha Ngwem +5 位作者 Cyrille Sigue Bepuaka Ekuka Martin Molua Ndive Alain Christian Bock Hyeng Emmanuel Yamb Sébastien Owona 《Open Journal of Civil Engineering》 2023年第2期388-398,共11页
The rapid economic growth of the town present the matter of water issue as a problem to human life human life, construction life, agriculture, etc. This study is to predict techniques of foundation construction throug... The rapid economic growth of the town present the matter of water issue as a problem to human life human life, construction life, agriculture, etc. This study is to predict techniques of foundation construction through the displaying of the water table at the flow direction in the town of Kumba and GIS. It is characterized by a significant research question which is the level of fall and rise in groundwater levels within the town of Kumba and this influence on choice of types of foundation in construction. This study is directed to decision makers, and technicians of the construction field to develop policies facilitating the supervision when building construction foundation by informing about water level depth and its flow direction in the town. To achieve this, depths of static water levels were measured in over 200 randomly selected hand-dug wells in Kumba, after their geolocation and data were collected during the dry season (November and March 2017) and during the rainy season (between April and October 2017). Data were analyzed and treated using Microsoft Excel and GIS software us as Golden Surfer, Global Mapper, and ArcGIS. The results show variations of water level and those areas that may threaten foundation construction. Quarter as Kumba Station, Mile 1, Bulletin Street (Fongong Quarter), and parts of Fiango show that water table is to deep water and proper for the shallow foundation but very hard for water supply through borehole. Groundwater flow direction was revealed to be towards the south and southeastern parts of Kumba. The significant of the study is to propose to the technician the direct application on the field of chosen types of foundations according to the quarter and proposed groundwater supply possibilities. 展开更多
关键词 GIS Prediction Water table Level Kumba FOUNDATION
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JTable组件的深入剖析 被引量:2
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作者 吴闻 《科技广场》 2012年第3期39-44,共6页
JTable组件是一个综合性的Java界面开发组件,内部包含一套独立的消息传递机制,以协调整个组件的运作。文中对JTable组件进行了深入的分析,介绍了JTable组件采用的设计模式、消息的传递方法、JTable的使用、TableModel的常用方法、如何向... JTable组件是一个综合性的Java界面开发组件,内部包含一套独立的消息传递机制,以协调整个组件的运作。文中对JTable组件进行了深入的分析,介绍了JTable组件采用的设计模式、消息的传递方法、JTable的使用、TableModel的常用方法、如何向JTable传递消息及如何实现对JTable的控制。最后,介绍了单元渲染器和编辑器的实现和使用。 展开更多
关键词 JAVA Jtable table Model CELL RENDER CELL EDITOR
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On-table重建技术配合微型钢板治疗桡骨小头粉碎性骨折22例疗效观察 被引量:6
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作者 王守宝 张振清 +3 位作者 杨峰 龚维成 崔丙军 曹霞 《疑难病杂志》 CAS 2013年第8期629-631,共3页
目的研究On-table重建技术配合微型钢板治疗MasonⅢ、Ⅳ型桡骨小头骨折的临床治疗效果。方法 2009年7月一2011年12月收治MasonⅢ或Ⅳ型桡骨小头骨折22例,男9例,女13例,年龄18~46岁。采用On-table重建技术与微型钢板予以切开复位内固定,... 目的研究On-table重建技术配合微型钢板治疗MasonⅢ、Ⅳ型桡骨小头骨折的临床治疗效果。方法 2009年7月一2011年12月收治MasonⅢ或Ⅳ型桡骨小头骨折22例,男9例,女13例,年龄18~46岁。采用On-table重建技术与微型钢板予以切开复位内固定,按Broberg和Morrey的肘关节功能评分标准进行临床评价。结果所有患者获得随访、中位时间12个月(10~18个月),肘关节功能评价:优7例,良13例,差2例,优良率90.9%。解剖复位9位,近似解剖复位13例。结论应用On-table重建技术配合微型钢板治疗桡骨小头粉碎性骨折(MasonⅢ、Ⅳ型),可达到良好的临床效果,但若骨折粉碎严重难以复位固定,可考虑行桡骨小头置换或切除。 展开更多
关键词 桡小骨头骨折 On—table重建技术 微型钢板
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1997版与2007版Partin tables预测国人前列腺癌病理分期准确性的比较 被引量:2
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作者 朱虹 章青 +1 位作者 吴登龙 傅深 《中国肿瘤临床》 CAS CSCD 北大核心 2008年第17期975-979,共5页
目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方法:选本院2003年1月至2007年9月间,116例前列腺癌患者经根治术后病理确诊为前列腺腺癌,术前资料具备前列摘要目的:验证2007版Partin table... 目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方法:选本院2003年1月至2007年9月间,116例前列腺癌患者经根治术后病理确诊为前列腺腺癌,术前资料具备前列摘要目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方腺特异抗原(prostate specific antigen,PSA),临床分期,穿刺活检Gleason评分。根据术后病理分为四型:器官局限(OC),包膜外侵犯(EPE),精囊侵犯(SVI)与淋巴结转移(LNI)。患者中93例符合2007版Partin tables预测入选标准,113例符合1997版预测入选标准,每例患者中分别应用两版Partintables预测术后病理特征的可能性,并通过工作特征曲线(ROC曲线)分析法研究两版Partintables的预测准确性并行比较。结果:根据2007版或1997版Partin tables预测入选标准,本组患者OC、EPE、SVI、LNI发生率分别为51%、15%、13%、22%或50%、16%、12%、23%。应用2007版Partin tables预测OC、EPE、SVI、LNI的ROC曲线下面积(AUC)分别为0.786、0.613、0.666和0.811,而应用1997版预测时分别为0.834、0.605、0.716、0.808。结论:两版Partin tables皆对OC及LNI有合理的预测价值(AUC>0.7),1997版Partin table比2007版显示出更佳的预侧准确性。 展开更多
关键词 前列腺肿瘤 Partin tableS 病理分期 试验预测值
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Physiological responses of Populus euphratica Oliv. to groundwater table variations in the lower reaches of Heihe River, Northwest China 被引量:6
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作者 Yang ZHAO ChuanYan ZHAO +5 位作者 ZhongLin XU YiYue LIU Yao WANG Chao WANG HuanHua PENG XiangLin ZHENG 《Journal of Arid Land》 SCIE 2012年第3期281-291,共11页
Riparian vegetation in the lower reaches of Heihe River serves important ecological functions. However, the riparian ecosystems have been constantly deteriorating in the past 30 years simply due to water interception ... Riparian vegetation in the lower reaches of Heihe River serves important ecological functions. However, the riparian ecosystems have been constantly deteriorating in the past 30 years simply due to water interception for oasis agricultural irrigation in the middle reaches of the river. This study pays a particular attention to Populus eu- phratica Oily. forest because it is a dominant component of the riparian ecosystem in the lower reaches of Heihe River where the depth of groundwater table is the controlling factor in sustaining riparian ecosystems. To reveal leaf-related physiological responses of Populus euphratica Oliv. forest to groundwater table variations, we analyzed the relationships between the depth of groundwater table (DG) and three leaf-related parameters, i.e. leaf stomatal density (SD), specific leaf area (SLA), and stable carbon isotopic composition (6~SC). Our results show that the relationship between DG and leaf SD is a bi-mode one shaped by both salt stress and water stress. That is, salt stress appeared in shallow groundwater conditions and water stress happened in deep groundwater conditions, and the thin layer around 2.7 m of DG is a stress-free layer. Leaf SD fluctuated according to the DG variation, first de- creased with increasing DG, then increased at depths ranging 2.7-3.7 m, and after a relatively stable plateau of SD at depths ranging 3.7-5.2 m, decreased again with increasing DG. Our results also show that SLA decreased ex- ponentially with increasing DG and foliar 6130 values are also strongly dependent on DG, further demonstrating that these two parameters are sensitive indicators of water stress. The exponential curve suggests that SLA is more sensitive to DG when groundwater table is shallow and 3 m seems to be a threshold beyond which SLA becomes less sensitive to DG. Foliar 613C becomes more sensitive when the groundwater table is deep and 7 m seems to be a threshold below which the 6130 signature becomes more sensitive to DG. These findings should be helpful in monitoring the growth and development of Populus euphratica Oliv. forests and also in providing protection measures (i.e. DG related) for Heihe River riparian forests. 展开更多
关键词 opulus euphratica Oily stable carbon isotopic composition stomatal density specific leaf area groundwater table
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浅谈table+css和div+css的区别 被引量:1
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作者 李忠健 《科技资讯》 2010年第14期19-19,共1页
网站的布局无非两种方式:div+css和table两种。这两种布局各有千秋,本文浅谈两者之间的不同点。
关键词 table DIV CSS 优缺点
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IPv6防火墙ip6tables过滤规则配置的图形界面设计
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作者 李晓峰 张玉清 李星 《计算机工程与应用》 CSCD 北大核心 2002年第23期116-117,140,共3页
IPv6的逐渐流行,将带来头痛的IPv6网络安全问题。Linux2.4内核中自带了IPv6防火墙软件———ip6tables,它以命令行的规则配置方式提供了齐全的IPv6过滤功能。但ip6tables的命令行方式,对用户来说使用非常不便,同时使得过滤规则的扩充和... IPv6的逐渐流行,将带来头痛的IPv6网络安全问题。Linux2.4内核中自带了IPv6防火墙软件———ip6tables,它以命令行的规则配置方式提供了齐全的IPv6过滤功能。但ip6tables的命令行方式,对用户来说使用非常不便,同时使得过滤规则的扩充和修改也极为繁琐。为了更为有效地配置IPv6防火墙过滤规则,笔者针对ip6tables设计了一个用过滤规则配置的图形界面,从而可以方便快捷地应用功能强大的ip6tables。 展开更多
关键词 IPV6协议 防火墙 ip6tables 过滤规则 图形界面 设计 网络安全 计算机网络 防火墙软件包
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Partin tables与Roach公式预测国人前列腺癌病理分期准确性的比较
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作者 朱虹 章青 +1 位作者 吴登龙 傅深 《肿瘤学杂志》 CAS 2008年第7期550-554,共5页
[目的]比较1997版、2007版Partin tables及Roach公式三种方式对国人前列腺癌患者病理特征预测的准确性。[方法]对116例患者应用1997版和2007版的Partin tables查出并利用Roach公式计算出术后病理分期,并通过工作特征曲线(ROC曲线)分析... [目的]比较1997版、2007版Partin tables及Roach公式三种方式对国人前列腺癌患者病理特征预测的准确性。[方法]对116例患者应用1997版和2007版的Partin tables查出并利用Roach公式计算出术后病理分期,并通过工作特征曲线(ROC曲线)分析法比较三种方式预测病理分期的准确性。[结果]应用1997版Partin tables预测器官局限,包膜外侵犯,精囊侵犯或淋巴结转移的ROC曲线下面积(AUC)分别为0.834、0.605、0.716、0.808,而2007版分别为0.786、0.613、0.666和0.811;Roach公式预测包膜外侵犯,精囊侵犯或淋巴结转移的AUC分别为0.495、0.712、0.754。[结论]3种预测方式综合比较,1997版Partin tables对前列腺癌病理特征预测的准确性最佳。 展开更多
关键词 前列腺肿瘤 Partin tableS 病理分期
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