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Effects of Long-term Located Fertilization on Wheat Yield and Soil Nutrients of Three Types of Soils in Shandong Province 被引量:1
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作者 张英鹏 刘兆辉 +3 位作者 李彦 仲子文 孙明 井永苹 《Agricultural Science & Technology》 CAS 2014年第3期400-406,426,共8页
[Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experi... [Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experiment in Jinan of Shandong Province was selected and the results of soil nutrient and crop yield in 1984, 1987, 1988, 1989, 1990, 2001, 2005, 2006, 2007 and 2010 were measured and collected. In this study, five treatments: CK, NP, NK, PK and NPK of the located experiment were selected. [Result] The three types of soils in wheat yields decreased signifi- cantly in the first several years and in 2006. Wheat yields of the treatments with P fertilizers were obviously higher than those without P fertilizers; it was shown that phosphorus is the primary nutritional factor for high-yielding of wheat. The highest yield is from cinnamon soil, followed by that from brown soil, and the lowest pro- duction is from fluvo-aquic soil. Under the same fertilization, the influence of other factors on wheat yield of brown soil is the smallest, while cinnamon soil is vulnera- ble to the influence of external conditions, resulting in larger fluctuation of annual wheat yield. The alkali-hydro nitrogen contents of three kinds of soils first de- creased, then raised, and at last reduced apparently. Since 2007, the change of al- kali-hydro nitrogen content appeared rebounded. The available P contents of no- phosphorus treatments decreased over time while those of the treatments with P fertilizers increased at first, then decreased, and after that kept relatively stable. The available K contents of no K treatments decreased slowly. The treatments of PK and NK had higher available K content than NPK treatment. [Conclusion] Thus, it is an effective fertilization measure to improve the wheat yield by supplying reasonable phosphate fertilizer and nitrogen fertilizer and making up potassium fertilizer. 展开更多
关键词 long-term located fertilization Brown soil Fluvo-aquic soil Cinnamon soil Wheat yield Soil nutrient
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Effects of Long-term Located Fertilization on the Contents and Composition of Organic Matter in Paddy Soil
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作者 卢志红 嵇素霞 +2 位作者 张美良 刘经荣 张结刚 《Agricultural Science & Technology》 CAS 2015年第10期2238-2242,共5页
To reveal variation of organic matter content in red paddy soil, Through a 27 years-located fertilization experiment in red paddy soil, the content and composi- tion of organic matter in paddy soil were studied in thi... To reveal variation of organic matter content in red paddy soil, Through a 27 years-located fertilization experiment in red paddy soil, the content and composi- tion of organic matter in paddy soil were studied in this paper. The result showed that: the dynamics of soil organic matter of the different fertilization treatments showed significant differences, in the premise of equal nutrient (nitrogen and phos- phorus and potassium), combining application of organic-inorganic was benefited for the accumulation of organic matter in paddy soil than without fertilizer treatment or chemical fertilizer treatment; the dynamics of soil humic acid, HA and FA of chemi- cal fertilizer only and Combining application of organic-inorganic treatments had basi- cally the same trend, But the contents of humic acid, HA and FA of combining ap- plication of organic-inorganic treatments had been higher than that without fertilizer and chemical fertilizer treatment. Moreover combining application of organic-inorganic treatments was benefited for improving the contents of HA and FA, but decreasing HA/FA ratio as an extension of time. Combining application of organic-inorganic was benefited for improving the contents ol readily oxidizable organic matter. And the contents of soil organic matter in long-term experiment and the contents of readily oxidizable O.M were highly significant positive correlation and the contents of soil total nitrogen, avail nitrogen and potassium were significant positive correlation; the contents of soil readily oxidizable O.M and the contents of soil total nitrogen, avail- able P and rice yield were significant positive correlation. Thereinto, the correlation (r=0.818 1 ) between the rice yield and soil readily oxidizable O.M was higher than the correlation (r=0.802 0) between the rice yield and soil organic matter. It showed the soil readily oxidized organic matter had greater contribution to the rice yield. 展开更多
关键词 long-term located fertilization Paddy soil Organic matter
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Effects of Long-term Located Fertilization on Evolution of Available Phosphorus and Phosphorus Pool in Shandong Fluvo-aquic Soil 被引量:1
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作者 Yingpeng ZHANG Gang DUAN +6 位作者 Cuiping SUN Ziwen ZHONG Ming SUN Yongping JING Jiafa LUO Luji BO Yan LI 《Agricultural Biotechnology》 CAS 2018年第2期74-80,共7页
This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change... This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change of Olsen-P to TP(PAC)by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil.Eight treatments were designed as no fertilization(CK),nitrogen fertilizer(N),nitrogen and phosphate fertilizer(NP),nitrogen and potassium fertilizer(NK),phosphate and potassium fertilizer(PK),nitrogen-phosphate-potassium fertilizer(NPK),reduced NPK fertilizer(N(15)PK),and increased NPK fertilizer(N_(25)PK).Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones.The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer.With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer.The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer.On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition.This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil. 展开更多
关键词 long-term located fertilization Fluvo-aquic soil Total phosphorus Available phosphorus Phosphorus pool Activity coefficient
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Effects of Long-term Located Fertilization on the Physico-chemical Property of Soil Humus
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作者 SHI Ji-ping, ZHANG Fu-dao and LIN Bao(School of Agriculture, Shanghai Jiao Tong University, Shanghai 201101 , P.R. China Soil and Fertilizer Inst. CAAS , Beijing 100081 , P.R. China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第4期424-431,共8页
A systematic study concerning the effects of a long-term stationary fertilization on content and property of soil humus in fluvo-aquic soil sampled from Malan Farm, Xinji City, Hebei, and arid red soil and paddy red s... A systematic study concerning the effects of a long-term stationary fertilization on content and property of soil humus in fluvo-aquic soil sampled from Malan Farm, Xinji City, Hebei, and arid red soil and paddy red soil sampled from the Institute of Red Soil, Jinxian County, Jiangxi was conducted. The results showed that long-term fertilization had effects not only on the content and composition of soil humus, but also on the physico-chemical property of humus. With applying organic manure or combined application of organic manure and chemical fertilizer, E4 and E6 values of humic acid decreased in fluvo-aquic soil and arid red soil, but increased in paddy red soil. In paddy red soil, E4 and E6 values of humic acid increased also with a single application of chemical fertilizer, but E4 and E6 values had less change of humic acid in fluvo-aquic soil and arid red soil. The effects on the visible spectroscopic property of f ulvic acid were different from that of humic acid. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase E4 and E6 values of f ulvic acid in three types of soil. Single application of chemical fertilizer had less effect on the E4 and E6. Long-term fertilization could also influence the ultraviolet spectroscopic property of humus. With a single application of organic manure or combined application of organic manure and chemical fertilizer, the ultraviolet absorbance of humic acid and f ulvic acid increased in the three types of soil. But this effect was obvious only in short wave length, and the effect could decrease if the wave length increased. With a single application of chemical fertilizer the ultraviolet absorbance of fulvic acid could increase, but it of humic acid increased only in fluvo-aquic soil. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase the content of total acidic groups, carboxy groups and phenolic hydroxy groups of humic acid and fuvic acid in the three types of soil. Single application of chemical fertilizer had less effect on the content of total acidic groups, carboxy groups and phenolic hydroxy groups of humic acid and fuvic acid in the three types of soil. 展开更多
关键词 long-term located fertilization Soil humus Fluvo-aquic soil Arid red soil Paddy red soil
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The Application of GGE Biplot Analysis for Evaluating Test Locations and Mega-Environment Investigation of Cotton Regional Trials 被引量:15
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作者 XU Nai-yin Fok Michel +2 位作者 ZHANG Guo-wei LI Jian ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1921-1933,共13页
In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to g... In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction(GGE) biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley(YaRV), China. Four traits(cotton lint yield, fiber length, lint breaking tenacity, micronaire) and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments: a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none. 展开更多
关键词 COTTON multi-environmental trial GGE biplot test location mega-environment
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GGE biplot analysis of yield stability and test location representativeness in proso millet (Panicum miliaceum L.) genotypes 被引量:14
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作者 ZHANG Pan-pan SONG Hui +8 位作者 KE Xi-wang JIN Xi-jun YIN Li-hua LIU Yang QU Yang SU Wang FENG Nai-jie ZHENG Dian-feng FENG Bai-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第6期1218-1227,共10页
The experiments were conducted for three consecutive years across 14 locations using 9 non-waxy proso millet genotypes and 16 locations using 7 waxy proso millet genotypes in China. The objectives of this study were t... The experiments were conducted for three consecutive years across 14 locations using 9 non-waxy proso millet genotypes and 16 locations using 7 waxy proso millet genotypes in China. The objectives of this study were to analyze yield stability and adaptability of proso millets and to evaluate the discrimination and representativeness of locations by analysis of vari- ance (ANOVA) and genotype and genotype by environment interaction (GGE) biplot methods. Grain yields of proso millet genotypes were significantly influenced by environment (E), genotype (G) and their interaction (GxE) (P〈0.1%). GxE inter- action effect was six times higher than G effect in non-waxy group and seven times in waxy group. N04-339 in non-waxy and Neimi 6 (NM6) in waxy showed higher grain yields and stability compared with other genotypes. Also, Neimi 9 (NM9, a non-waxy cultivar) and 90322-2-33 (a waxy cultivar) showed higher adaptability in 7 and in 11 locations, respectively. For non-waxy, Dalat, Inner Mongolia (E2) and Wuzhai, Shanxi (E5) were the best sites among all the locations for maximizing the variance among candidate cultivars, and Yanchi, Ningxia (El0) had the best representativeness. Wuzhai, Shanxi (e9) and Yanchi, Ningxia (e14) were the best representative locations, and Baicheng, Jilin (e2) was better discriminating location than others for waxy genotypes. Based on our results, El0 and e14 have enhanced efficiency and accuracy for non-waxy genotypes and waxy genotypes selection, respectively in national regional test of proso millet varieties. 展开更多
关键词 proso millet GGE biplot yield stability test location representativeness
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One-sided empirical Bayes test for location parameter in Gamma distribution 被引量:1
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作者 YUAN Min ZHANG Qian WEI Lai-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第3期287-297,共11页
In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is as... In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is asymptotically optimal with the rate of the order O(n^(-δs/(2s+1))), where 1/2 ≤ δ < 1 and s > 1 is a given natural number. An example is also given to illustrate that the conditions of the main theorems are easily satisfied. 展开更多
关键词 three parameter Gamma distribution location parameter one-sided empirical Bayes test asymptotically optimality convergence rate
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Mitigation of Low Frequency Oscillations by Optimal Allocation of Power System Stabilizers: Case Study on MEPE Test System
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作者 Wai Myat Thu Kyaw Myo Lin 《Energy and Power Engineering》 2018年第8期333-350,共18页
The increases in power network and weak tie-line have led power system oscillation problems. To improve the oscillatory stability, installing the power system stabilizer (PSS) with optimal allocation is considered due... The increases in power network and weak tie-line have led power system oscillation problems. To improve the oscillatory stability, installing the power system stabilizer (PSS) with optimal allocation is considered due to excessive cost. This paper recommends the suitable PSS locations by using eigenvalue analysis and participation factor to enhance the system oscillation damping. The effects of installed PSSs in damping local and inter-area modes of oscillations are confirmed through time domain simulation results. The effectiveness of proposed approach is tested and validated on MEPE test system. Robustness of stabilizers against dynamic response of generator speed deviation, rotor angle deviation, and response of mechanical power are observed to access the performances of PSSs. 展开更多
关键词 EIGENVALUE Analysis MEPE test System OSCILLATION Mode Optimal location of PSS PARTICIPATION Factor
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Research on location of underground explosion center based on distributed testing system
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作者 WANG Tian-hao ZHANG Zhi-jie CHENG Hao 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第2期112-117,共6页
Distributed testing system has strong applicability in the field of dynamic testing,which can centrally manage the testing equipment in different locations through the local area network,and meet the new requirements ... Distributed testing system has strong applicability in the field of dynamic testing,which can centrally manage the testing equipment in different locations through the local area network,and meet the new requirements of the test.Based on the theory of seismic location,the location of underground explosion center was studied.The applicability of seismic location theory to the location of underground explosion center was verified by simulating the underground explosion with LS-DYNA simulation platform.Combined with distributed testing system theory and weighting method,the optimal distribution method of test points was summarized through data analysis. 展开更多
关键词 explosion center location LS-DYNA distributed testing system seismic location weighting method
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Tests for Two-Sample Location Problem Based on Subsample Quantiles
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作者 Parameshwar V. Pandit Savitha Kumari S. B. Javali 《Open Journal of Statistics》 2014年第1期70-74,共5页
This paper presents a new class of test procedures for two-sample location problem based on subsample quantiles. The class includes Mann-Whitney test as a special case. The asymptotic normality of the class of tests p... This paper presents a new class of test procedures for two-sample location problem based on subsample quantiles. The class includes Mann-Whitney test as a special case. The asymptotic normality of the class of tests proposed is established. The asymptotic relative performance of the proposed class of test with respect to the optimal member of Xie and Priebe (2000) is studied in terms of Pitman efficiency for various underlying distributions. 展开更多
关键词 U-STATISTIC Class of testS Two-Sample location Problem Asymptotic NORMALITY Pitman ARE Subsample QUANTILES
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Long-Term Loading Test of Reinforced Glulam Beam
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作者 Nan Guo Jing Ren +2 位作者 Ling Li Yan Zhao Mingtao Wu 《Journal of Renewable Materials》 SCIE EI 2022年第1期183-201,共19页
Due to creep characteristics of wood,long-term loading can cause a significant stress loss of steel bars in rein-forced glulam beams and high long-term deflection of the beam midspan.In this study,15 glulam beams were... Due to creep characteristics of wood,long-term loading can cause a significant stress loss of steel bars in rein-forced glulam beams and high long-term deflection of the beam midspan.In this study,15 glulam beams were subjected to a 90-day long-term loading test,and the effects of long-term loading value,reinforcement ratio and prestress level on the stress of steel bars,midspan long-term deflection,and other parameters were compared and analyzed.The main conclusions drawn from this study were that the long-term deflection of the reinforced glulam beams accounted for 22.5%,20.6%,and 18.2%of the total deflection respectively when the loading value was 20%,30%,and 40%of the estimated ultimate load under the long-term loading.The higher the loading level was,the smaller the proportion of the long-term deflection in the total deflection was.Compared with ordinary glulam beams,the long-term deflection of the reinforced glulam beam was even smaller.Under the condition of the constant loading level,the total stress value of the steel bars decreased by 17.5%,13.6%,and 9.1%,and the proportion of the long-term deflection of the beam midspan in the total deflection was 26.9%,24.2%,and 20.6%respectively when the reinforcement ratio was 2.05%,2.68%,and 3.39%.With the increase of the reinfor-cement ratio,the stress loss of the steel bars decreased,and the proportion of the long-term deflection decreased as well.When other conditions remained constant and the prestress level of the steel bars was 0 MPa,30 MPa,and 60 MPa,the total stress value of the steel bars decreased by 9.1%,9.4%,and 10.2%,respectively,and the propor-tion of the long-term deflection in the total deflection was 20.6%,26.1%,and 64.9%,respectively.With the increase of the prestress value,the stress loss of the steel bars increased,and the proportion of the long-term deflection increased as well. 展开更多
关键词 Reinforced glulam beams long-term loading tests creep characteristics PRESTRESS total stress of steel bars
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Improved fault location method for AT traction power network based on EMU load test
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作者 Guosong Lin Xuguo Fu +1 位作者 Wei Quan Bin Hong 《Railway Engineering Science》 2022年第4期532-540,共9页
The autotransformer(AT)neutral current ratio method is widely used for fault location in the AT traction power network.With the development of high-speed electrified railways,a large number of data show that the relat... The autotransformer(AT)neutral current ratio method is widely used for fault location in the AT traction power network.With the development of high-speed electrified railways,a large number of data show that the relation between the AT neutral current ratio and the distance from the beginning of the fault AT section to the fault point(Q-L relation)is mostly nonlinear.Therefore,the linear Q-L relation in the traditional fault location method always leads to large errors.To solve this problem,a large number of load-related current data that can be used to describe the Q-L relation are obtained through the load test of the electric multiple unit(EMU).Thus,an improved fault location method based on the back propagation(BP)neural network is proposed in this paper.On this basis,a comparison between the improved method and the traditional method shows that the maximum absolute error and the average absolute error of the improved method are 0.651 km and 0.334 km lower than those of the traditional method,respectively,which demonstrates that the improved method can effectively eliminate the influence of nonlinear factors and greatly improve the accuracy of fault location for the AT traction power network.Finally,combined with a shortcircuit test,the accuracy of the improved method is verified. 展开更多
关键词 Fault location EMU load test BP neural network AT traction power network High-speed electrified railway
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Effect of Specific Verbal Instructions on the Identification of Pain Location during a Passive Straight Leg Raise Test
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作者 Masae Ikeya Takumi Jiroumaru +2 位作者 Hitomi Bunki Noriyuki Kida Teruo Nomura 《Open Journal of Therapy and Rehabilitation》 2023年第2期45-53,共9页
Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests... Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests quickly and accurately. Simple and clear instructions are recommended for pain assessment. However, few studies have provided evidence to support this hypothesis. Correspondingly, this study aimed to confirm the effectiveness of specific verbal instructions for pain location during five consecutive Passive Straight Leg Raise (PSLR) tests. The 28 asymptomatic participants (age 27.4 ± 9.6 years) who provided informed consent received five consecutive PSLR tests: three without and two with specific verbal instructions to ascertain pain intensity, quality, and location. The participants drew pain locations on a body chart and described the pain intensity and quality after each test. All participants were interviewed regarding the differences they noted in the presence and absence of specific verbal instructions. Each pain location was classified into one of ten areas for statistical analysis. The proportion of participants who changed the pain location was compared between the tests using McNemar’s test, and the kappa coefficient was confirmed for consistency of pain location. There was a significant difference in the proportion of participants who changed their pain location between the second and third tests and from the third to the fourth test (McNemar’s test: p = 0.003). Kappa coefficients had low consistency (κ = 0.28) just after receiving the specific verbal instructions in the fourth test compared to the third test. Consistency improved in the fifth test (κ = 0.57);93% of the participants answered that the pain location had become clearer. This study revealed the effects of specific verbal instructions in identifying pain locations. This detailed information may help PTs provide appropriate treatment and contribute to reducing pain in clinical settings. 展开更多
关键词 Specific Verbal Instructions Pain location Pain Assessment Passive Straight Leg Raise test
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Clinical Significance of Pulmonary Function Tests in Long-Term Survivors after Myeloablative Allogeneic Hematopoietic Stem Cell Transplantation
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作者 Kenji Matsumoto Satomi Ito +4 位作者 Wataru Yamamoto Eriko Ogusa Atsuo Maruta Yoshiaki Ishigatsubo Heiwa Kanamori 《Open Journal of Blood Diseases》 2013年第1期6-12,共7页
We retrospectively assessed long-term pulmonary function in adults surviving for ≥5 years after myeloablative allogeneic hematopoietic stem cell transplantation and identified risk factors for late-onset noninfectiou... We retrospectively assessed long-term pulmonary function in adults surviving for ≥5 years after myeloablative allogeneic hematopoietic stem cell transplantation and identified risk factors for late-onset noninfectious pulmonary complications. Among 174 patients undergoing transplantation for hematologic malignancies between May 1994 and December 2004, 81 long-term survivors were evaluated. Pulmonary function tests (PFTs) were performed before conditioning, 3 months and 1 year after transplantation, and then annually. Eight patients (10%) had abnormal pulmonary function before transplantation, but this was not associated with late changes in PFTs. Patients with chronic graft-versus-host disease (GVHD) showed a significant decline of lung function after 3 years when compared with patients without chronic GVHD. Abnormal pretransplantation lung function was associated with pulmonary chronic GVHD according to National Institutes of Health criteria (score 0, n = 58;score 1, n = 14;score 2, n = 6;score 3, n = 3). Five patients with late-onset noninfectious pulmonary complications showed a decline of lung function at 1 year after transplantation. Only chronic GVHD was significantly related to late-onset noninfectious pulmonary complications. In conclusion, abnormal lung function before transplantation may be associated with a decline in pulmonary function within 1 year after transplantation, but late-onset noninfectious pulmonary complications could not be predicted from pretransplantation lung function. 展开更多
关键词 long-term SURVIVOR PULMONARY Function tests LATE-ONSET Noninfectious PULMONARY COMPLICATIONS MYELOABLATIVE ALLOGENEIC Stem Cell Transplantation
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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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A Trajectory Privacy Protection Method to Resist Long-Term Observation Attacks
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作者 Qixin Zhan 《Journal of Computer and Communications》 2024年第5期53-70,共18页
Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exp... Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exploited by opponents, greatly increasing the risk of trajectory privacy leakage. This attack method is called a long-term observation attack. On the premise of ensuring lower time overhead and higher cache contribution rate, the existing methods cannot utilize cache to answer subsequent queries while also resisting long-term observation attacks. So this article proposes a trajectory privacy protection method to resist long-term observation attacks. This method combines caching technology and improves the existing differential privacy mechanism, while incorporating randomization factors that are difficult for attackers to recognize after long-term observation to enhance privacy. Search for locations in the cache of both the mobile client and edge server that can replace the user’s actual location. If there are replacement users in the cache, the query results can be obtained more quickly. Simultaneously obfuscating the spatiotemporal correlation of actual trajectories by generating confusion regions. If it does not exist, the obfuscated location generation method that resists long-term observation attacks is executed to generate the real anonymous area and send it to the service provider. The above steps can comprehensively protect the user’s trajectory privacy. The experimental results show that this method can protect user trajectories from long-term observation attacks while ensuring low time overhead and a high cache contribution rate. 展开更多
关键词 location Privacy long-term Observation Attacks K-ANONYMITY location Caching
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Model test and numerical simulation on the dynamic stability of the bedding rock slope under frequent microseisms 被引量:9
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作者 Deng Zhiyun Liu Xinrong +4 位作者 Liu Yongquan Liu Shulin Han Yafeng Liu Jinhui Tu Yiliang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第4期919-935,共17页
Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability... Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability under purely microseisms and the influence of five factors, including seismic amplitude, slope height, slope angle, strata inclination and strata thickness, were considered. The experimental results show that the natural frequency of the slope decreases and damping ratio increases as the earthquake loading times increase. The dynamic strength reduction method is adopted for the stability evaluation of the bedding rock slope in numerical simulation, and the slope stability decreases with the increase of seismic amplitude, increase of slope height, reduction of strata thickness and increase of slope angle. The failure mode of a mid-dip bedding rock slope in the shaking table test is integral slipping along the bedding surface with dipping tensile cracks at the slope rear edge going through the bedding surfaces. In the numerical simulation, the long-term stability of a mid-dip bedding slope is worst under frequent microseisms and the slope is at risk of integral sliding instability, whereas the slope rock mass is more broken than shown in the shaking table test. The research results are of practical significance to better understand the formation mechanism of reservoir landslides and prevent future landslide disasters. 展开更多
关键词 bedding rock slope frequent microseisms shaking table test numerical simulation dynamic stability failure mode long-term stability
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Current Trends and Perspectives of Detection and Location for Buried Non-Metallic Pipelines 被引量:6
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作者 Liang Ge Changpeng Zhang +6 位作者 Guiyun Tian Xiaoting Xiao Junaid Ahmed Guohui Wei Ze Hu Ju Xiang Mark Robinson 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第5期118-146,共29页
Buried pipelines are an essential component of the urban infrastructure of modern cities.Traditional buried pipes are mainly made of metal materials.With the development of material science and technology in recent ye... Buried pipelines are an essential component of the urban infrastructure of modern cities.Traditional buried pipes are mainly made of metal materials.With the development of material science and technology in recent years,non-metallic pipes,such as plastic pipes,ceramic pipes,and concrete pipes,are increasingly taking the place of pipes made from metal in various pipeline networks such as water supply,drainage,heat,industry,oil,and gas.The location technologies for the location of the buried metal pipeline have become mature,but detection and location technologies for the non-metallic pipelines are still developing.In this paper,current trends and future perspectives of detection and location of buried non-metallic pipelines are summarized.Initially,this paper reviews and analyzes electromagnetic induction technologies,electromagnetic wave technologies,and other physics-based technologies.It then focuses on acoustic detection and location technologies,and finally introduces emerging technologies.Then the technical characteristics of each detection and location method have been compared,with their strengths and weaknesses identified.The current trends and future perspectives of each buried non-metallic pipeline detection and location technology have also been defined.Finally,some suggestions for the future development of buried non-metallic pipeline detection and location technologies are provided. 展开更多
关键词 Non-metallic pipeline Pipeline detection and location Non-destructive test and evaluation Acoustic technologies
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Location Verification Systems in Emerging Wireless Networks 被引量:5
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作者 Shihao Yan Robert Malaney 《ZTE Communications》 2013年第3期3-10,共8页
As location-based techniques and applications have become ubiquitous in emerging wireless networks, the verification of location information has become more important. In recent years, there has been an explosion of a... As location-based techniques and applications have become ubiquitous in emerging wireless networks, the verification of location information has become more important. In recent years, there has been an explosion of activity related to lo- cation-verification techniques in wireless networks. In particular, there has been a specific focus on intelligent transport systems because of the mission-critical nature of vehicle location verification. In this paper, we review recent research on wireless location verification related to vehicular networks. We focus on location verification systems that rely on for- mal mathematical classification frameworks and show how many systems are either partially or fully encompassed by such frameworks. 展开更多
关键词 location verification wireless networks likelihood ratio test decision rule
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Long-Term Bending Behaviour of Prestressed Glulam Bamboo-Wood Beam Based on Creep Effect 被引量:4
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作者 Nan Guo Huajing Xiong +4 位作者 Mingtao Wu Hongliang Zuo Fengguo Jiang Xiaofeng Hou Dabo Xin 《Structural Durability & Health Monitoring》 EI 2020年第3期229-248,共20页
Creep is an important characteristic of bamboo and wood materials under long-term loading.This paper aims to study the long-term bending beha-viour of prestressed glulam bamboo-wood beam(GBWB).For this,14 pre-stressed... Creep is an important characteristic of bamboo and wood materials under long-term loading.This paper aims to study the long-term bending beha-viour of prestressed glulam bamboo-wood beam(GBWB).For this,14 pre-stressed GBWBs were selected and subjected to a long-term loading test for 60 days.Then,a comparative analysis was performed for the effects of pre-tension values,the number of pre-stressed wires,and long-term load on the stress variation of the steel wire and the long-term deflection of the beam midspan.The test results showed that with the number of prestressed wires increasing,the total stress of the steel wire in the beam midspan and the ratio of the long-term deflec-tion to the total deflection decreases decreased,but when the number of steel wires exceeded 4,the total stress and long-term deflection was less infuenced;with the pre-tension value increasing,the ratio of the total stress of the steel wire in the beam midspan and the ratio of the long-temm deflection to the total deflec-tion also decreased,but when the prestress force was greater than 3.975 kN,the:total stress and long-term deflection were less affected;with the other parameters unchanged,when the value of the long-term load increased,the total stress of the steel wire decreased,and the long-temm deflection of the beam midspan increased,which shall be more significant with the long-term load greater than 30%of the standard ultimate bearing capacity.After the test,the experimental data were fitted,and the creep coefficient was given.Finally,the long-term stiffness calcula-tion fommula of the pre-stressed GBWB based on creep effect was proposed.The research findings have certain theoretical significance and engineering value. 展开更多
关键词 Prestressed glulam bamboo-wood beam long-temn loading test steel wire stress long-term deflection creep cofficient
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