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Novel models for simulating maize growth based on thermal time and photothermal units: Applications under various mulching practices 被引量:1
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作者 LIAO Zhen-qi ZHENG Jing +4 位作者 FAN Jun-liang PEI Sheng-zhao DAI Yu-long ZHANG Fu-cang LI Zhi-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1381-1395,共15页
Maize (Zea mays L.) is one of the three major food crops and an important source of carbohydrates for maintaining food security around the world.Plant height (H),stem diameter (SD),leaf area index (LAI) and dry matter... Maize (Zea mays L.) is one of the three major food crops and an important source of carbohydrates for maintaining food security around the world.Plant height (H),stem diameter (SD),leaf area index (LAI) and dry matter (DM) are important growth parameters that influence maize production.However,the combined effect of temperature and light on maize growth is rarely considered in crop growth models.Ten maize growth models based on the modified logistic growth equation (Mlog) and the Mitscherlich growth equation (Mit) were proposed to simulate the H,SD,LAI and DM of maize under different mulching practices based on experimental data from 2015–2018.Either the accumulative growing degree-days (AGDD),helio thermal units (HTU),photothermal units (PTU) or photoperiod thermal units (PPTU,first proposed here) was used as a single driving factor in the models;or AGDD was combined with either accumulative actual solar hours (ASS),accumulative photoperiod response (APR,first proposed here) or accumulative maximum possible sunshine hours (ADL) as the dual driving factors in the models.The model performances were evaluated using seven statistical indicators and a global performance index.The results showed that the three mulching practices significantly increased the maize growth rates and the maximum values of the growth curves compared with non-mulching.Among the four single factor-driven models,the overall performance of the Mlog_(PTU)Model was the best,followed by the Mlog_(AGDD)Model.The Mlog_(PPTU)Model was better than the Mlog_(AGDD)Model in simulating SD and LAI.Among the 10 models,the overall performance of the Mlog_(AGDD–APR)Model was the best,followed by the Mlog_(AGDD–ASS)Model.Specifically,the Mlog_(AGDD–APR)Model performed the best in simulating H and LAI,while the Mlog_(AGDD–ADL)and Mlog_(AGDD–ASS)models performed the best in simulating SD and DM,respectively.In conclusion,the modified logistic growth equations with AGDD and either APR,ASS or ADL as the dual driving factors outperformed the commonly used modified logistic growth model with AGDD as a single driving factor in simulating maize growth. 展开更多
关键词 THERMAL time ACCUMULATIVE growing DEGREE-DAYS helio THERMAL UNITS PHOTOTHERMAL UNITS growth model
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Microbial Growth and Decay: A Commented Review of the Model
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作者 Alberto Schiraldi 《Advances in Microbiology》 CAS 2024年第1期1-10,共10页
The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathem... The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathematical expressions, the paper highlights the reasons for the choice of a suitable time origin that makes the parameters of the model self-consistent. Besides the potential applications to predictive microbiology studies and to effects of bactericidal drugs, the model allows a suitable proxy of the fitness of the microbial culture, which can be of interest for the studies on the evolution across some thousand generations of a Long Term Evolution Experiment. 展开更多
关键词 Microbial Cultures MODEL time Scale growth and Decay EVOLUTION
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Quantifying the natural growth rate of hepatocellular carcinoma:A real-world retrospective study in southwestern China
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作者 Li Tu Hong Xie +6 位作者 Qi Li Ping-Gui Lei Pei-Ling Zhao Fan Yang Chi Gong Yuan-Lin Yao Shi Zhou 《World Journal of Hepatology》 2024年第5期800-808,共9页
BACKGROUND In recent years,approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma(HCC)have been reported in China.Despite the high incidence of HCC,there remains a pauci... BACKGROUND In recent years,approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma(HCC)have been reported in China.Despite the high incidence of HCC,there remains a paucity of data regarding the natural growth pattern and the determination of optimal surveillance intervals specific to the Chinese population.AIM To quantify the natural tumor growth pattern of HCC in regional China.METHODS A retrospective analysis was performed on patients from a single institution in Southwest China who had undergone two or more serial dynamic computed tomography or magnetic resonance imaging scans between 2014 and 2020,without having received any anti-cancer therapy.Tumor growth was assessed using tumor volume doubling time(TVDT)and tumor growth rate(TGR),with volumes measured manually by experienced radiologists.Simple univariate linear regression and descriptive analysis were applied to explore associations between growth rates and clinical factors.RESULTS This study identifies the median TVDT for HCC as 163.4 d,interquartile range(IQR)72.1 to 302.3 d,with a daily TGR of 0.42%(IQR 0.206%-0.97%).HCC growth patterns reveal that about one-third of tumors grow indolently with TVDT exceeding 270 d,another one-third of tumors exhibit rapid growth with TVDT under 90 d,and the remaining tumors show intermediate growth rates,with TVDT ranging between 3 to 9 months.CONCLUSION The identified TGRs support biannual surveillance and follow-up for HCC patients in certain regions of China.Given the observed heterogeneity in HCC growth,further investigation is warranted. 展开更多
关键词 Hepatocellular carcinoma Natural tumor growth pattern Tumor volume doubling time Tumor growth rate Realworld retrospective study
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Influence of water logging time on the growth of Kandelia candel seedlings 被引量:18
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作者 CHENLuzhen WANGWenqing LINPeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第1期149-157,共9页
Influence of waterlogging time on the growth of Kandelia candel(L.) Druce seedlings grown for 70 d in the artificial- tidal tanks' simulated semidiurnal tide under greenhouse is studied. Sand and soil act as the s... Influence of waterlogging time on the growth of Kandelia candel(L.) Druce seedlings grown for 70 d in the artificial- tidal tanks' simulated semidiurnal tide under greenhouse is studied. Sand and soil act as the substrate and artificial seawater with salinity of 15 is used in cultivation. Shorter waterlogging time(inundated for about 2 ~ 4 h) promotes the growth of K. candel seedlings, while longer time(inundated more than 8 h) or no waterlogging(0 h) inhibits their growth. The number and length of aerating roots increase with the increase of waterlogging time. Under existing conditions, the optimal waterlogging time for the growth of K. candel seedlings is about 2 ~ 4 h in every tide cycle. Compared with other treatments, the 2 h sanded treatments obtain the highest biomass of seedlings, have the lowest mass loss of hypocotyl and broaden the photosynthetic area by increasing the area per leaf after 70-d cultivation. And the soil treatments have the similar tendency. However, waterlogging for 8 h in every tide cycle is critical for normal development of seedlings.K. candel seedlings are highly tolerant to waterlogging and a proper waterlogging is beneficial to the growth of K. candel seedlings. 展开更多
关键词 K. candel growth optimal waterlogging time critical waterlogging time
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EFFECT OF MAGNETIZATION OF WATER ON INDUCTION TIME AND GROWTH PERIOD OF NATURAL GAS HYDRATE 被引量:4
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作者 KUANG Li and FAN Shuanshi(Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510070, Guangdong, China) 《化工学报》 EI CAS CSCD 北大核心 2003年第z1期81-85,共5页
The effect of diluted solution's magnetization on induction time and growth period of natural gas hydrate (NGH) has been investigated in quiescent reaction system at pressure of 4. 5 MPa and temperature of 274 K w... The effect of diluted solution's magnetization on induction time and growth period of natural gas hydrate (NGH) has been investigated in quiescent reaction system at pressure of 4. 5 MPa and temperature of 274 K with SDS as surfactant, by using volume fixed and pressure falling method. Experimental results show that magnetization will have effect on the induction time of NGH. After magnetization with magnetic field intensity of 0.33 T, the induction time of NGH has been reduced to 47 min (average) from 99 min (average) in which there is no magnetization. On the other hand, the induction time has been prolonged after magnetization of the diluted solution with magnetic field intensity of 0.05 T, 0. 11 T, 0.22 T, 0.44T. Especially with magnetic field intensity of 0.11 T, the induction time had even been prolonged to 431min (average). The effect of magnetization on the growth period of NGH has not been found at the experimental condition. 展开更多
关键词 NATURAL GAS hydrate magnetization growth INDUCTION time
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Influences of noise correlation and time delay on stochastic resonance induced by multiplicative signal in a cancer growth system 被引量:4
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作者 贾正林 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期113-118,共6页
This paper investigates the stochastic resonance (SR) phenomenon induced by the multiplicative periodic signal in a cancer growth system with the cross-correlated noises and time delay. To describe the periodic chan... This paper investigates the stochastic resonance (SR) phenomenon induced by the multiplicative periodic signal in a cancer growth system with the cross-correlated noises and time delay. To describe the periodic change of the birth rate due to the periodic treatment, a multiplicative periodic signal is added to the system. Under the condition of small delay time, the analytical expression of the signal-to-noise ratio RSNR is derived in the adiabatic limit. By numerical calculation, the effects of the cross-correlation strength λ and the delay time τ on RSNR are respectively discussed. The existence of a peak in the curves of RSNR as a function of the noise intensities indicates the occurrence of the SR phenomenon. It is found that λ and τ play opposite role on the SR phenomenon, i.e., the SR is suppressed by increasing λ whereas it is enhanced with the increase of τ, which is different from the case where the periodic signal is additive. 展开更多
关键词 time delay cross-correlated noise stochastic resonance cancer growth system
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利用TIMESAT软件和时间序列卫星影像提取新疆石河子棉花种植区域 被引量:4
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作者 魏瑞琪 李林峰 +2 位作者 仙巍 邵怀勇 汪盾 《湖北农业科学》 2018年第4期105-112,共8页
以新疆石河子市2014年的MOD13Q1为数据源,利用遥感技术处理获得NDVI时间序列数据集,运用TIMESAT软件集成的拟合方法[非对称高斯函数(A-G)拟合、双Logistic曲线(D-L)拟合和Savitzky-Golay(S-G)滤波法]对石河子市棉花像元的时间序列数据... 以新疆石河子市2014年的MOD13Q1为数据源,利用遥感技术处理获得NDVI时间序列数据集,运用TIMESAT软件集成的拟合方法[非对称高斯函数(A-G)拟合、双Logistic曲线(D-L)拟合和Savitzky-Golay(S-G)滤波法]对石河子市棉花像元的时间序列数据集进行棉花生长曲线拟合对比,最终选取效果较理想的D-L滤波法对石河子市NDVI时间序列集处理,获取石河子棉花生长曲线,分析棉花生长曲线的特点,提取棉花生长的NDVI阈值,进而提取石河子市的棉花种植区域。结果表明,利用TIMESAT软件和时间序列卫星资料提取棉花种植区域效果好、精度高。MODIS数据分辨率适中,成像面积大,利用时间序列卫星资料获取生长曲线进行棉花信息提取,对大范围的棉花种植监测和农业经济指导具有重要意义。 展开更多
关键词 遥感 timesAT 时间序列 NDVI 生长曲线
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Formalin fixation on HER-2 and PD-L1 expression in gastric cancer:A pilot analysis using the same surgical specimens with different fixation times 被引量:4
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作者 Keita Kai Yukie Yoda +4 位作者 Atsushi Kawaguchi Akimichi Minesaki Hironori Iwasaki Shinichi Aishima Hirokazu Noshiro 《World Journal of Clinical Cases》 SCIE 2019年第4期419-430,共12页
BACKGROUND The needs for human epidermal growth factor receptor 2(HER-2) and/or programmed death-ligand 1(PD-L1) evaluations in gastric cancer are dramatically increasing. Although the importance of standardization of... BACKGROUND The needs for human epidermal growth factor receptor 2(HER-2) and/or programmed death-ligand 1(PD-L1) evaluations in gastric cancer are dramatically increasing. Although the importance of standardization of sample fixation has been widely recognized, most of the evidence regarding the fixation duration or type of fixing solution are based on breast cancer.AIM To investigate the real effects of fixation conditions on HER-2 testing or PD-L1 testing for gastric cancer using gastrectomy specimens.METHODS Thirty-two patients who underwent gastrectomy for gastric cancer were enrolled.Their resected specimens were each divided into four pieces and fixed in four strictly controlled different durations(6 h, 24 h, and 48 h, and 1 wk) by 10%formalin(n = 22) or 10% neutral buffered formalin(NBF)(n = 10).Immunohistochemistry(IHC) of HER-2 and PD-1 was performed, and a pathology examination was conducted. In the HER-2-immunoreactive cases, all four specimens were subjected to dual-color in situ hybridization(DISH). Five cases were assessed as HER-2-positive by IHC and DISH. We used the cut-off values of 1%, 10%, and 50% to assess the IHC findings of PD-L1.RESULTS No significant difference was observed in comparisons between the shorter fixation period groups(6 h, 24 h, and 48 h) and the prolonged fixation period(1 wk) group in the HER-2 and PD-L1 analyses. Although no significant difference was observed between 10% formalin and 10% NBF within 1 wk of fixation, the superiority of 10% NBF was confirmed in a long-term(> 3 mo) fixation in both the HER-2 and PD-L1 analyses.CONCLUSION In this small-numbered pilot study, prolonged fixation within 1 wk showed no inferiority in HER-2 or PD-L1 testing. However, a large-numbered prospective study is needed to obtain conclusive results. 展开更多
关键词 GASTRIC cancer Programmed death-ligand1 Human EPIDERMAL growth factor receptor2 Neutral buffered FORMALIN FIXATION time
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Influence of Reaction Time on Growth Behaviours of Mg-Al LDH Films
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作者 吴量 CHEN Jing +5 位作者 ZHANG Sheng TANG Ai-tao YANG Dan-ni ZHANG Gen LIU Lei 潘复生 《表面技术》 EI CAS CSCD 北大核心 2019年第3期19-26,共8页
Mg-Al LDH film was fabricated on anodized magnesium alloy AZ31 by in-situ growth method.The characteristics of the film were investigated by X-ray diffraction(XRD),Fourier transform infrared(FT-IR),scanning electron m... Mg-Al LDH film was fabricated on anodized magnesium alloy AZ31 by in-situ growth method.The characteristics of the film were investigated by X-ray diffraction(XRD),Fourier transform infrared(FT-IR),scanning electron microscopy(SEM)observation and electrochemical tests.The results showed that the crystallinity of LDH film was increased with reaction time.When the reaction time was more than 12 h,the LDH film had complete crystal layered structure.The anodic oxide film was sealed basically by the growth of LDH nanosheets after 6 h reaction.The corrosion resistance of the films became better with the increasing of reaction time.However,after 12 h reaction,the corrosion resistance of the film decreased.The formation behavior of the Mg-Al LDH film was proposed.That the competitive growth of LDH grains,which contains dissolution and recrystallization,was proposed to explain the change of the growth and corrosion resistance of the Mg-Al LDH film. 展开更多
关键词 magnesium alloy corrosion resistance in-situ growth LAYERED double hydroxide(LDH) reaction time
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Effects of Feeding Time on the Growth Performance and Variation of RNA/DNA Ratio of the Chinese Soft-shelled Turtle, Pelodiscus sinensis
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作者 Yingguang jI Haiyan LIU +1 位作者 Zhe SONG Zhencai YANG 《Asian Herpetological Research》 SCIE CSCD 2016年第4期271-277,共7页
The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00... The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00 and off at 18:00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00:00, 04:00, 08:00, 12:00, 16:00 and 20:00 with 60 turtles each (Initial body weight 88.27 - 0.09 g). Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate (SGR) and RNA/ DNA:SGR=t.1586RNA/DNA-0.7097 (r = 0.9328, P = 0.0066). The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12:00 were the lowest from the six groups (P 〈 0.05). Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight (FBW), higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total. 展开更多
关键词 Feeding time growth performance Pelodiscus sinensis RNA/DNA ratio
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Crack growth time dependence analysis of granite under compressive-shear stresses state
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作者 李江腾 曹平 +1 位作者 古德生 吴超 《Journal of Coal Science & Engineering(China)》 2008年第1期34-37,共4页
The curves of crack relative length lib and crack growth time t of granite were gained under compressive stresses state according to subcritical crack growth parameters and crack stability growth equation by double-to... The curves of crack relative length lib and crack growth time t of granite were gained under compressive stresses state according to subcritical crack growth parameters and crack stability growth equation by double-torsion constant displacement load relaxa- tion method. The relations between crack relative length and the crack growth time were discussed under different stresses and different crack lengths. The results show that there is a turning point on curve of crack relative length lib and crack growth time of granite. The slope of curve is small when crack relative length is less than the vertical coordinate of the point, and crack grows stably in this case. Cracks grow, encounter and integrate catastro- phically when crack relative length is more than the vertical coordinate of the point, and there is not a gradual stage from crack stability growth to crack instability growth, i.e. rock mass instability is sudden. The curves of crack relative length lib and crack growth time t of granite move to right with decrease of stress σl or crack length a, which implies that limit time increases consequently. The results correspond to practicality. 展开更多
关键词 GRANITE compressive-shear stresses state crack stability growth time de-pendence limit time
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Effects of Spatial Row Arrangement and Time of Planting Intercrops on Performance of Groundnut (Arachis hypogaea L.) under Maize (Zea mays L.)—Groundnut Intercropping System in Ejura
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作者 Fuseini Bawaror Bugilla Kwadwo Gyasi Santo +3 位作者 Abdul Aziz Khalid Daniel Ntiamoah Afreh Kwabena Atakora Muntala Abdulai 《American Journal of Plant Sciences》 CAS 2023年第3期264-289,共26页
In monoculture, crop failure due to biotic or abiotic causes can result in partial or total output failure. The yield, socio-economic, and environmental effects of intercropping on the farmer and the environment as a ... In monoculture, crop failure due to biotic or abiotic causes can result in partial or total output failure. The yield, socio-economic, and environmental effects of intercropping on the farmer and the environment as a whole have not received much attention. There is a dearth of knowledge on the productivity of maize-groundnut intercrops in Ghana regarding the relative timing of planting and spatial arrangement of component crops. Therefore, the objective of the study was to determine the effects of spatial row arrangement and the time of planting intercrops on the productivity of groundnut under maize-groundnut intercropping. The 5 × 3 factorial field experiment was undertaken at the Miminaso community in the Ejura-Sekyedumase municipality of the Ashanti Region of Ghana during the 2020 cropping seasons. Treatments were evaluated in a Randomized Complete Block Design (RCBD) with three replicates. The levels of row arrangement of intercrops were: one row of maize and one row of groundnut (1M1G), one row of maize and two rows of groundnut (1M2G), two rows of maize and one row of groundnut (2M1G), two rows of maize and two rows of groundnut (2M2G), sole maize and sole groundnut (M/G). The levels of time of introducing groundnut included simultaneous planting of intercrops (0 WAP), planting groundnut one week after planting maize (1 WAP) and planting groundnut two weeks after planting maize (2 WAP). There were significant (P 0.05) treatment interactions for pod and seed yields of groundnut throughout the study. The highest groundnut pod yields of 1815.00 kg/ha and 2359.00 kg/ha were recorded by the 0WAP × 1M2G treatment in the major and minor seasons of 2020, respectively, while the highest groundnut seed yields of 741.00 kg/ha and 726.00 kg/ha were recorded in the major and minor rainy seasons of 2020 by 1WAP × G and 0WAP × G treatments, respectively. The highest seed yields of groundnut (404 kg/ha and 637 kg/ha for major and minor rainy seasons, respectively) were produced by 1WAP × 2M2G. 展开更多
关键词 INTERCROPPING GROUNDNUT MAIZE growth Yield time Row Arrangement
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天然气管道可靠性增长预测方法研究 被引量:2
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作者 张鹏 宋文琦 +2 位作者 肖博文 刘为 赵明 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第1期114-120,共7页
为减少天然气管道投产前的设计和制造缺陷,提高使用寿命、运行可靠性和安全性、减少后期维修费用,通过统计模型结合试验数据实现对天然气管道可靠性增长水平的预测,提出天然气管道可靠性增长预测方法;分析常用可靠性增长模型并结合天然... 为减少天然气管道投产前的设计和制造缺陷,提高使用寿命、运行可靠性和安全性、减少后期维修费用,通过统计模型结合试验数据实现对天然气管道可靠性增长水平的预测,提出天然气管道可靠性增长预测方法;分析常用可靠性增长模型并结合天然气管道可维修、小子样的特点,将Duane模型与AMSAA模型应用于天然气管道,结合点估计、趋势检验、拟合优度检验、区间估计和标准差,得出天然气管道可靠性增长模型,预测可靠性增长并进行实例验证。研究结果表明:Duane模型与AMSAA模型作为天然气管道可靠性增长试验具有可行性;其中AMSAA模型更具优势,得出天然气管道的瞬时无故障工作时间(MTBF)估计值可达到试验目标值,并预测MTBF达到2000 h时所需要的试验时间为317954611.3 h,未来第51次故障预测区间为[848.4609,939.6226],误差为1.25%,方法具有良好的适用性,可有效预测天然气管道可靠性增长。研究结果可为天然气管道设计改进提供指导。 展开更多
关键词 天然气管道 可靠性增长 DUANE模型 AMSAA模型 MTBF
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浸种方式和浸种时间对木薯种茎吸水及茎段幼苗生长的影响
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作者 黄洁 王娟 +2 位作者 魏云霞 刘丽娟 李天 《江西农业学报》 CAS 2024年第5期1-6,共6页
选用木薯品种华南205的长种茎(1.8 m长),采用平浸(平放完全浸泡)和竖浸(浸基部10.0 cm)2种清水浸种方式,分别设置0、6、12、18、24 h共5个浸种时间,以不浸种(0 h)为对照,研究了不同浸种处理后种茎的含水量变化及其基部、中部和顶部3类... 选用木薯品种华南205的长种茎(1.8 m长),采用平浸(平放完全浸泡)和竖浸(浸基部10.0 cm)2种清水浸种方式,分别设置0、6、12、18、24 h共5个浸种时间,以不浸种(0 h)为对照,研究了不同浸种处理后种茎的含水量变化及其基部、中部和顶部3类部位短茎段(15.0 cm长)栽植后幼苗的生长情况。结果表明:随着浸种时间的延长,长种茎的吸水率均显著提高,而吸水速率显著降低;平浸处理的种茎含水量增加量、吸水率和吸水速率分别比竖浸处理显著提高了0.53、3.65、0.29个百分点;竖浸处理的短茎段的出苗率、株高、茎径、根径、茎叶鲜重及茎叶干重均显著高于平浸处理的;浸种12 h处理和不浸种对照的短茎段的幼苗株高、茎径、根数、茎叶鲜重及茎叶干重均优于其他浸种时间处理的;基部和中部茎段栽植的幼苗株高、茎径、单株叶片数、根数、根径、茎叶鲜重、茎叶干重及芽数占比均显著高于顶部茎段栽植的。推荐木薯长种茎以竖浸方式浸种12 h,并采用经浸种处理的长种茎的基部和中部短茎段进行栽植。 展开更多
关键词 木薯 种茎 浸种方式 浸种时间 吸水 苗期 生长
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微尺度下润湿性表面对双气泡传热特性的影响
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作者 战洪仁 纪柏辰 +3 位作者 刘东灵 刘德彬 张先珍 李帅 《化学工程》 CAS CSCD 北大核心 2024年第5期13-18,38,共7页
为探究混合润湿表面双气泡生长过程的特点和传热特性,利用格子Boltzmann方法研究混合润湿性表面不同因素对生长和传热过程的影响规律。结果表明:对于纯润湿性表面,随着润湿性的降低,气泡成核时间减少,气泡脱离表面时间呈增加趋势,双气... 为探究混合润湿表面双气泡生长过程的特点和传热特性,利用格子Boltzmann方法研究混合润湿性表面不同因素对生长和传热过程的影响规律。结果表明:对于纯润湿性表面,随着润湿性的降低,气泡成核时间减少,气泡脱离表面时间呈增加趋势,双气泡生长过程的平均热流密度呈减少趋势。混合表面可以实现相比纯润湿性表面更高的脱离频率和更好的换热效果,混合润湿表面整体脱离频率在(L_(q)/△x)>0.37(△x<30)时呈增加趋势,在(L_(q)/△x)≤0.37(△x≥30)时呈降低趋势;同一距离L_(q)/△x不同疏水尺寸的脱离频率在(L_(q)/△x)>0.37(△x<30)时呈先降低后增加趋势,在(L_(q)/△x)≤0.37(△x≥30)时呈增加趋势;同一距离L_(q)/△x不同疏水尺寸的平均热流密度在(L_(q)/△x)>0.37(△x<30)时呈降低趋势,L_(s)=3(L_(s)/L_(q)=0.27)是最佳换热尺寸,在(L_(q)/△x)≤0.37(△x≥30)时呈先增加后降低趋势,L_(s)=5(L_(s)/L_(q)=0.45)为最佳换热尺寸。 展开更多
关键词 格子BOLTZMANN 混合润湿性 生长过程 换热效果 脱离时间
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“996”还是“2.5”?——闲暇时间影响经济增长的跨国实证研究
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作者 罗浩 康玉洁 曾小梅 《旅游学刊》 CSSCI 北大核心 2024年第1期147-163,共17页
近年来,社会上掀起了“996工作制”和“2.5天小长假”的激烈讨论。为了避免价值判断,文章在文献梳理和理论演绎的基础上,利用41个较大规模国家的面板数据,检验了闲暇数量和质量对经济增长的影响,按经济发展水平和文化地理特征分别对样... 近年来,社会上掀起了“996工作制”和“2.5天小长假”的激烈讨论。为了避免价值判断,文章在文献梳理和理论演绎的基础上,利用41个较大规模国家的面板数据,检验了闲暇数量和质量对经济增长的影响,按经济发展水平和文化地理特征分别对样本国家分组并进行异质性分析。研究结果显示:闲暇时间与经济增长之间存在一定的非线性特征,闲暇时间比例在0.6608至0.6855区间下经济增长率明显较高;整体而言,人力资本对闲暇时间与经济增长的关系存在显著的正向调节作用,数量闲暇一旦与人力资本相结合(即质量闲暇)很可能促进经济增长。研究结果对我国的政策含义是:既不“996”也不“2.5”,保持闲暇时间比例不变,减少工作时间比例而增加教育时间比例,既能提升人力资本直接推动经济增长,又能通过人力资本改善闲暇质量从而间接推动经济增长。 展开更多
关键词 闲暇时间 经济增长 非线性 人力资本 调节作用
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NM23基因与非小细胞肺癌临床病理学特征及^(18)F-FDG PET/CT影像特征的相关性
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作者 夏露花 崇乐 +4 位作者 李红玉 郭鹏 董占飞 王新华 常诚 《分子影像学杂志》 2024年第4期348-352,共5页
目的 比较非小细胞肺癌中NM23基因表达情况不同在其临床病理学特征、^(18)F-FDG PET/CT影像特征、生存时间的差异。方法 选择2018年1月~2022年12月于新疆医科大学附属医院病理确诊为非小细胞癌的107例患者的术后标本,运用免疫组化方法检... 目的 比较非小细胞肺癌中NM23基因表达情况不同在其临床病理学特征、^(18)F-FDG PET/CT影像特征、生存时间的差异。方法 选择2018年1月~2022年12月于新疆医科大学附属医院病理确诊为非小细胞癌的107例患者的术后标本,运用免疫组化方法检测NM23表达情况,分为NM23低表达组(≤++)(n=64)与NM23高表达组(>++)(n=43),比较两组的临床病理学特征、^(18)FFDG FDG PET/CT图像上影像特征、生存期方面的差异。结果 NM23低表达组与高表达组在性别、临床分期、组织类型、分化程度、吸烟、PET/CT图像上生长部位、生存时间的差异无统计学意义(P>0.05),但在原发灶分期、PET/CT图像上淋巴结转移情况的差异有统计学意义(P<0.05)。结论 NM23基因在非小细胞癌患者T分期、淋巴结转移方面支持其为抑癌基因。 展开更多
关键词 非小细胞肺癌 NM23基因 临床病理学特征 正电子发射断层显像 生长部位 生存时间
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融合时序分类的科技领域实体增长预测研究
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作者 陈果 陈智力 陈霜澜 《情报理论与实践》 CSSCI 北大核心 2024年第2期116-123,共8页
[目的/意义]科技领域实体增长机制是进行预测型科技情报分析的核心,要有效地进行科技发展态势感知和预测,必须深入了解科技领域细粒度知识增长机制。文章提出并验证了融合时序分类的科技领域实体增长预测方案。[方法/过程]首先,根据实... [目的/意义]科技领域实体增长机制是进行预测型科技情报分析的核心,要有效地进行科技发展态势感知和预测,必须深入了解科技领域细粒度知识增长机制。文章提出并验证了融合时序分类的科技领域实体增长预测方案。[方法/过程]首先,根据实体词频时间序列的增长模式,将实体分为可拟合、有趋势和无规律3种类别;其次,利用曲线拟合、局部加权回归方法抽取特征,构建特征向量,再用MLP模型实现了高精度的实体分类;最后,构建融合时序分类的集成模型与基线模型进行对比验证效果。[结果/结论]根据实验结果,验证显示集成预测模型相对于基线模型,误差减少了13%以上,进一步证实了预测结果在科学性和准确性方面的优势。综合考虑,所提出的融合时间序列分类的实体增长预测方案在可行性和应用价值方面具备潜力。 展开更多
关键词 时间序列分类 领域实体 实体增长预测 集成模型
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《莫失莫忘》的成长叙事与伦理反思
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作者 胡作友 卢逸凡 《山东科技大学学报(社会科学版)》 2024年第4期113-120,共8页
石黑一雄在《莫失莫忘》中抛弃了常规的线性时间序列,转而采用现在与过去交替并行的波形叙事时间结构,使人物在回忆与现实中来回穿梭,在情感的跌宕起伏中推动情节的展开。克隆人生活在“惩戒规训”和“调节控制”泛滥的社会,虽然有从自... 石黑一雄在《莫失莫忘》中抛弃了常规的线性时间序列,转而采用现在与过去交替并行的波形叙事时间结构,使人物在回忆与现实中来回穿梭,在情感的跌宕起伏中推动情节的展开。克隆人生活在“惩戒规训”和“调节控制”泛滥的社会,虽然有从自我意识到思想启蒙的成长,但逃避不了从空间隔绝到暴力政治带来的生命权利的反成长。小说中的时间结构与成长叙事融为一体,把过去与现在连接起来,将梦想与现实交错呈现,实现了人与物从“现实”之此岸到“过去”之彼岸与从“过去”之彼岸到“现实”之此岸的跨越。波形时间建构的非线性叙事彰显了善意与恶意、希望与绝望、成长与反成长的对抗,引起读者对后现代社会中人的存在与意义的反思。 展开更多
关键词 波形时间结构 成长叙事 石黑一雄 《莫失莫忘》 伦理反思
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当摄影遇见文字:《盲刺客》中的“摄影书写”
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作者 吕晓潇 《山东科技大学学报(社会科学版)》 2024年第5期106-112,共7页
后现代语境下,摄影被赋予了复杂的指意系统,给阐释留下多元空间。在《盲刺客》中,阿特伍德将摄影巧妙融入叙事,使之成为串联核心主题的重要隐喻。摄影以转喻形式构成一种记忆诗学,是主人公回顾与反思家族历史的记忆媒介;照片着色与“左... 后现代语境下,摄影被赋予了复杂的指意系统,给阐释留下多元空间。在《盲刺客》中,阿特伍德将摄影巧妙融入叙事,使之成为串联核心主题的重要隐喻。摄影以转喻形式构成一种记忆诗学,是主人公回顾与反思家族历史的记忆媒介;照片着色与“左手”写作都代表一种超现实主义视角,在探索女性精神依存及主体生成的同时,书写了象征自由与创造的“另一个宇宙空间”;摄影的幽灵性则凸显主人公的写作回忆录是一个与死者协商的过程。阿特伍德通过“摄影书写”唤起读者对被遗忘或压抑记忆的关注,引导读者以多元视角重构历史认知,并认识到摄影艺术所蕴含的解放潜能,同时揭示历史与未来的辩证关系,启迪人们只有在对过去的理解和反思中才能寻找到未来的希望。 展开更多
关键词 《盲刺客》 摄影书写 记忆 身份 历史
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