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Dynamic Responses of Super Rice IIyou602 Plants to Different Nitrogen Levels and Configuration Modes 被引量:1
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作者 姜心禄 郑家国 +3 位作者 池忠志 李旭毅 牟中林 李涛 《Agricultural Science & Technology》 CAS 2012年第3期574-577,共4页
[Objective] The paper was to study the dynamic responses of super rice Ilyou602 plants to different nitrogen levels and configuration modes. [Method] With super rice Ilyou602 as test material, the dynamic changes of t... [Objective] The paper was to study the dynamic responses of super rice Ilyou602 plants to different nitrogen levels and configuration modes. [Method] With super rice Ilyou602 as test material, the dynamic changes of total N content in functional leaves, leaf sheaths and stems under different, application amount of nitrogen and configuration modes were analyzed. [Result] The highest total N content of functional leaves under different N levels appeared in the different periods, which was the highest during rehydration period in A3 level. The total N content in various plant positions during full heading stage and maturity stage showed fertilization treatments 〉 CK, functional leaves 〉 leaf sheaths 〉 stems. The total N content in different plant positions showed obvious difference in different treatments. When the super rice Ilyou602 was planted in Chengdu plain, the proper application level of N and configuration mode was as follows: 165 kg/hm2, fertilizer: topdressing = 6:4. [Conclusion] The study provided theoretical basis for nitrogen regulation of high yield cultivation of super hybrid rice. 展开更多
关键词 n levels Configuration modes Super rice Dynamic response
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Combined effect of shading time and nitrogen level on grain filling and grain quality in japonica super rice 被引量:18
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作者 WEI Hai-yan ZHU Ying +9 位作者 QIU Shi HAN Chao HU Lei XU Dong ZHOU Nian-bing XING Zhi-peng HU Ya-jie CUI Pei-yuan DAI Qi-gen ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第11期2405-2417,共13页
There is limited information about the combined effect of shading time and nitrogen (N) on grain filling and quality of rice. Therefore, two japonica super rice cultivars, Nanjing 44 and Ningjing 3, were used to stu... There is limited information about the combined effect of shading time and nitrogen (N) on grain filling and quality of rice. Therefore, two japonica super rice cultivars, Nanjing 44 and Ningjing 3, were used to study the effect of shading time and N level on the characteristics of rice panicle and grain filling as well as the corresponding yield and quality. At a low N level (150 kg N ha^-1, 150N), grain yield decreased (by 21.07-26.07%) under the treatment of 20 days of shading before heading (BH) compared with the no shading (NS) treatment. These decreases occurred because of shortened panicle length, decreased number of primary and secondary branches, as well as the grain number and weight per panicle. At 150N, in the treatment of 20 days of shading after heading (AH), grain yield also decreased (by 9.46-10.60%) due to the lower grain weight per panicle. The interaction of shading and N level had a significant effect on the number of primary and secondary branches. A high level of N (300 kg N ha^-1, 300N) could offset the negative effect of shading on the number of secondary branches and grain weight per panicle, and consequently increased the grain yield in both shading treatments. In superior grains, compared with 150N NS, the time to reach 99% of the grain weight (T99) was shortened by 1.6 to 1.7 days, and the grain weight was decreased by 4.18-5.91% in 150N BH. In 150N AH, the grain weight was 13.39-13.92% lower than that in 150N NS due to the slow mean and the maximum grain-filling rate (GRmean and GRmax). In inferior grains, grain weight and GRmean had a tendency of 150N NS〉150N BH〉150N AH. Under shaded conditions, 300N decreased the grain weight due to lower GReen both in superior and inferior grains. Compared with 150N NS, the milling and appearance qualities as well as eating and cooking quality were all decreased in 150N BH and 150N AH. Shading with the high level of 300N improved the milling quality and decreased the number of chalky rice kernels, but the eating and cooking quality was reduced with increased chalky area and overall chalkiness. Therefore, in the case of short term shading, appropriate N fertilizer could be used to improve the yield and milling quality of rice, but limited application of N fertilizer is recommended to achieve good eating and cooking quality of rice. 展开更多
关键词 shading time n levels grain filling rice quality japonica super rice
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Influence of Nitrogen Levels and Application Methods on Yield and Quality of Sorghum
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作者 A.RASHID R.U.KHAN H.ULLAH 《Pedosphere》 SCIE CAS CSCD 2008年第2期236-241,共6页
A field study was conducted for two years at the Arid Zone Research Institute, Dera Ismail Khan, Pakistan, to determine the optimum level of nitrogen and efficient application method in the production of sorghum (Sor... A field study was conducted for two years at the Arid Zone Research Institute, Dera Ismail Khan, Pakistan, to determine the optimum level of nitrogen and efficient application method in the production of sorghum (Sorghum bicolor L.). Using four levels of nitrogen, i.e., 0, 60, 90, and 120 kg ha^-1, and two different application methods (soil application and foliar spray), the experiment was laid out in a split-plot design, where the main plots were used to determine the effective method of application and the subplots were used to detect the influence of N levels on the grain yield. The average data obtained after two years of study indicated an increase in the grain yields with an increase in N levels irrespective of the method used of N application. The grain yield increased from 2.92 to 5.61 t ha^-1 in the plots that were treated with 90 kg N ha^-1 compared with the control plots. Quadratic regression analysis showed that the increase in the yield was higher at the lower levels of N compared with the succeeding higher levels. The soil application method, producing an average grain yield of 4.79 t ha^-1, was found to be superior to the foliar spray method with an average grain yield of 4.56 t ha^-1. The protein content of the grain showed a linear increase with N application, attaining the maximum at 120 kg N ha^-1 in both the methods of N application. In addition, compared with the method of soil application, higher crude protein contents were observed using the method of foliar spray at all N levels. 展开更多
关键词 foliar spray grain yield n level protein content soil application
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Integrated Action of Mixture Rates and Nitrogen Levels on Quantity and Quality of Forage Mixture from Egyptian Clover and Barley in Sandy Soil 被引量:1
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作者 Mohamed Farouk El-Karamany Bakry Ahmed Bakry Tarek Abd El-Fattah Elewa 《Agricultural Sciences》 2014年第14期1539-1546,共8页
Effect of seeding rate mixture from Egyptian clover (Trifolium alexandrinum L.) E.C. and barley (Hordum vulgare L.) B, N-fertilization levels and their interaction on quantity and quality of forage yield. Two field ex... Effect of seeding rate mixture from Egyptian clover (Trifolium alexandrinum L.) E.C. and barley (Hordum vulgare L.) B, N-fertilization levels and their interaction on quantity and quality of forage yield. Two field experiments were conducted during winter season of 2012/2013 and 2013/2014 in sandy soil at research and production station of National Research Centre, Al Nubaria district, Al Behaira Governorate, Egypt. The experiment included two factors first was five mixtures from seeding rates (24 kg EC/fed. – 50 kg B/fed. – 18 kg EC + 12.5 kg B/fed. – 12kg EC + 25 kg B/fed. – 6 kg EC + 37.5 kg B/fed.) and second factor was three N levels (30-45-60 kg N/fed.). Two cuts were obtained at 60 and 100 DAS. Results indicated significant differences between mixture rates for all studied characters in both cuts 60 and 100 DAS. Significant differences between N levels for all studied characters at 60 DAS, also, forage yield /fed. and DM% at 100 DAS. It can be introducing forage mixture of 18 kg EC + 12.5 B had balanced character in forage yield/fed., DM%, carbohydrate % and protein % at both cuts 60 and 100 DAS. 展开更多
关键词 FORAGE MIXTURE EGYPTIAn CLOVER BARLEY n-levels
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“1+3+N”多层次医疗保障体系协同发展研究——基于待遇给付视角 被引量:3
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作者 胡宏伟 刘堂森 《中国医疗保险》 2025年第4期5-12,共8页
“1+3+N”多层次医疗保障体系协同发展是提升医疗保障待遇水平的重要途径。在厘清多层次医疗保障体系待遇给付次序的形成路径后发现,给付次序的优化根本上依赖于基本医保“三重保障”和“其他保障力量”各层次错位协同发展,实现“目标... “1+3+N”多层次医疗保障体系协同发展是提升医疗保障待遇水平的重要途径。在厘清多层次医疗保障体系待遇给付次序的形成路径后发现,给付次序的优化根本上依赖于基本医保“三重保障”和“其他保障力量”各层次错位协同发展,实现“目标协同、功能错位、内容互补”的目标。具体而言,“三重保障”要以制度整合为方向,持续推进医保筹资机制和支付方式改革,在“充分的保基本”目标基础上进一步促进健康公平;传统商业健康险要坚持以“多元医疗需求满足”为核心的错位发展,致力于群众差异化医疗需求保障;惠民保和职工互助保障要坚持以“基本医疗费用补偿”为核心的错位发展,弥补基本制度重特大疾病保障不足的缺口。 展开更多
关键词 1+3+n 多层次医疗保障 待遇给付 错位协同
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NAC联合BiPAP无创呼吸机对COPD合并呼吸衰竭患者血气指标及炎症指标水平的影响
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作者 朱戈 李晓倩 白兆青 《分子诊断与治疗杂志》 2025年第8期1440-1443,共4页
目的探讨N-乙酰半胱氨酸(NAC)联合双水平无创正压通气(BiPAP)无创呼吸机对慢性阻塞性肺疾病(COPD)合并呼吸衰竭患者血气指标及炎症指标水平的影响。方法回顾性分析2021年1月至2024年1月在安庆市立医院就诊的92例COPD合并呼吸衰竭患者的... 目的探讨N-乙酰半胱氨酸(NAC)联合双水平无创正压通气(BiPAP)无创呼吸机对慢性阻塞性肺疾病(COPD)合并呼吸衰竭患者血气指标及炎症指标水平的影响。方法回顾性分析2021年1月至2024年1月在安庆市立医院就诊的92例COPD合并呼吸衰竭患者的临床资料。按照治疗方式的不同分为对照组(n=50)与实验组(n=42)。对照组患者常规给予平喘、抗感染、BiPAP无创呼吸机治疗,实验组在此基础上给予NAC治疗,均持续治疗7 d。比较两组的临床疗效、肺功能指标[用力肺活量占预计值百分比(FVC%pred)、1 s用力呼气容积占预计值的百分比(FEV_(1)%pred)、FVC与FEV_(1)比值(FVC/FEV_(1))]、血气指标[动脉血氧分压(PaO_(2))、动脉血二氧化碳(PaCO_(2))、血氧饱和度(SaO_(2))]、炎症指标[降钙素原(PCT)、C反应蛋白(CRP)]以及不良反应。结果实验组治疗有效率为92.86%高于对照组78.00%,差异有统计学意义(P<0.05)。治疗7 d末实验组FEV_(1)%pred、FVC%pred、FVC/FEV_(1)、PaO_(2)、SaO_(2)显著高于同组治疗前且组间比较高于对照组同期,差异有统计学意义(P<0.05);治疗7 d末实验组PaCO_(2)、PCT、CRP显著低于同组治疗前且组间比较低于对照组同期,差异有统计学意义(P<0.05)。两组不良反应率为11.90%vs 8.00%比较差异无统计学意义(P>0.05)。结论NAC联合BiPAP无创呼吸机可提高COPD合并呼吸衰竭患者治疗有效率,改善患者肺功能、血气指标,减轻炎症反应且安全性良好。 展开更多
关键词 n-乙酰半胱氨酸 双水平无创正压通气 慢性阻塞性肺疾病 呼吸衰竭 血气指标
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培哚普利联合氨氯地平对原发性高血压伴左心室肥厚的逆转作用及对患者血浆N末端B型利钠肽原水平的影响 被引量:5
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作者 张金春 王朝霞 李志华 《陕西医学杂志》 CAS 2025年第1期109-113,共5页
目的:探究培哚普利联合氨氯地平对原发性高血压伴左心室肥厚的逆转作用及对血浆N末端B型利钠肽原(NT-ProBNP)水平的影响。方法:选择原发性高血压伴左心室肥厚患者138例为研究对象,按随机数表法分为三组,均46例。对照组1予以氨氯地平治疗... 目的:探究培哚普利联合氨氯地平对原发性高血压伴左心室肥厚的逆转作用及对血浆N末端B型利钠肽原(NT-ProBNP)水平的影响。方法:选择原发性高血压伴左心室肥厚患者138例为研究对象,按随机数表法分为三组,均46例。对照组1予以氨氯地平治疗,对照组2予以培哚普利治疗,观察组采用培哚普利联合氨氯地平治疗。比较临床疗效、治疗前后血压情况、舒张末期左室内径(LVDd)、室间隔厚度(I与T)、左室后壁厚度(PWT)、左室重量指数(LVMI)及NT-ProBNP、同型半胱氨酸(Hcy)心钠肽(ANP)水平。结果:观察组总有效率为95.65%(44/46)高于对照组1[80.43%(37/46)]和对照组2[76.09%(35/46)](均P<0.05),对照组1和对照组2比较无统计学差异(P>0.05)。治疗前,三组收缩压、舒张压、I与T、PWT、LVMI及血清NT-ProBNP、Hcy、ANP水平比较,差异无统计学意义(均P>0.05),治疗后,观察组收缩压(127.87±13.66与136.46±15.73与135.00±15.98)、舒张压(81.07±5.58与83.98±7.16与85.57±7.22)、LVDd(46.48±2.24与48.37±3.62与48.30±3.57)、I与T(10.00±1.38与11.20±1.50与11.24±1.55)、PWT(10.52±1.35与12.24±1.40与12.37±1.39)、LVMI(124.57±10.80与145.13±10.27与144.93±10.34)、NT-ProBNP(64.53±15.63与75.23±18.46与78.15±18.54)、Hcy(8.93±2.68与15.48±4.66与14.88±4.62)、ANP(139.95±38.64与216.84±59.15与213.87±59.23)水平均较对照组1和对照组2下降(均P<0.05),对照组1和对照组2比较无统计学差异(P>0.05)。结论:培哚普利联合氨氯地平对原发性高血压伴左心室肥厚治疗效果较好,可有效降低血压、改善左室相关指标,并降低NT-Pro BNP水平。 展开更多
关键词 培哚普利 氨氯地平 原发性高血压伴左心室肥厚 血浆n末端B型利钠肽原水平 逆转作用
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系统性红斑狼疮患者外周血CD14^(+)CD16^(+)单核细胞和IgG N-糖基化水平与疾病活动度的相关性研究
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作者 刘建晓 董月稳 +4 位作者 刘向芹 陈世成 薛云 王天赐 张凯 《现代检验医学杂志》 2025年第5期88-93,共6页
目的研究系统性红斑狼疮(SLE)患者外周血CD14^(+)CD16^(+)单核细胞和IgG N-糖基化水平与疾病活动度相关性。方法回顾性选取2021年8月~2024年11月邢台市中心医院收治的109例SLE患者作为研究对象。根据SLE疾病活动指数(SLE-DAI)将患者分... 目的研究系统性红斑狼疮(SLE)患者外周血CD14^(+)CD16^(+)单核细胞和IgG N-糖基化水平与疾病活动度相关性。方法回顾性选取2021年8月~2024年11月邢台市中心医院收治的109例SLE患者作为研究对象。根据SLE疾病活动指数(SLE-DAI)将患者分为活动组(n=52)和稳定组(n=57),另选取同期进行健康体检者56例为对照组。收集纳入者临床资料,通过流式细胞仪(FCM)检测CD14^(+)CD16^(+)单核细胞,亲水相互作用色谱-质谱联用检测IgG N-糖基水平;Logistic回归分析SLE-DAI的影响因素,对自变量进行多重共线性检验[方差膨胀因子(VIF)];构建疾病活动度的预测模型,通过描绘受试者工作特征(ROC)曲线并计算曲线下面积(AUC)值评估预测模型的效能;Hosmer-Lemeshow拟合优度检验预测模型校准度。结果对照组WBC,Hb,PLT,ALB,补体C3,补体C4水平高于SLE组(t=8.917~22.171),而C反应蛋白(CRP)水平低于SLE组(t=-17.359),差异具有统计学意义(均P<0.05);活动组CRP水平和CD14^(+)CD16^(+)单个核细胞比例高于稳定组,差异具有统计学意义(t=5.449,11.112,均P<0.05);活动组IgG N-糖基化特征中半乳糖基化、唾液酸化、平分型N-乙酰葡糖胺修饰均低于稳定组,差异具有统计学意义(Z=-2.361,-2.12,-2.432,均P<0.05)。Spearman相关分析显示,CD14^(+)CD16^(+)单核细胞比例与IgG半乳糖基化、唾液酸化水平、平分型N-乙酰葡糖胺修饰呈显著负相关(r=-0.656,-0.531,-0.608,均P<0.01),CD14^(+)CD16^(+)单核细胞比例与SLE-DIA呈正相关(r=0.581,均P<0.01);IgG半乳糖基化、唾液酸化水平、平分型N-乙酰葡糖胺修饰与SLE-DIA呈负相关(r=-0.645,-0.609,-0.503,均P<0.01)。Logistic回归分析,CRP>8.21mg/L,CD14^(+)CD16^(+)≥16.17%,唾液酸化<22.05%,平分型N-乙酰葡糖胺修饰<16.53%是SLE患者疾病活动度的独立危险因素(Waldχ^(2)=4.471~12.811,均P<0.05),且上述自变量的VIF值均小于10;通过建立Logistic回归预测模型并绘制ROC曲线,计算得出诊断SLE-DIA的AUC值为0.821(95%CI:0.733~0.905),灵敏度、特异度和约登指数分别为85.37%,75.67%,0.677;Hosmer-Lemeshow拟合优度检验模型P值为0.568。结论SLE患者外周血CD14^(+)CD16^(+)单核细胞比例显著增加,IgG N-糖基化特征水平降低,均与SLE-DIA具有相关性,基于二者构建的预测模型区分SLE疾病活动与非活动状态的能力良好,高灵敏度和适中特异度利于临床早期识别,模型拟合效果好,能较准确评估SLE-DAI。 展开更多
关键词 系统性红斑狼疮 CD14^(+)CD16^(+)单核细胞 IgG n-糖基化水平 疾病活动度
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基于离子交换色谱的高唾液酸N糖谱测定方法的建立
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作者 尹红锐 方欣欣 +3 位作者 张颖 徐明明 郑璐侠 邵泓 《中国药品标准》 2025年第4期366-370,共5页
目的:建立基于离子交换色谱的高唾液酸N糖谱测定方法。方法:采用阴离子交换色谱柱(4.6 mm×250 mm,5μm,或等效的色谱柱);以20%乙腈溶液为流动相A,以0.1 mol·L^(-1)甲酸铵的20%乙腈溶液(pH 4.5)为流动相B,流速0.60 mL·min... 目的:建立基于离子交换色谱的高唾液酸N糖谱测定方法。方法:采用阴离子交换色谱柱(4.6 mm×250 mm,5μm,或等效的色谱柱);以20%乙腈溶液为流动相A,以0.1 mol·L^(-1)甲酸铵的20%乙腈溶液(pH 4.5)为流动相B,流速0.60 mL·min^(-1);荧光检测器检测,激发波长为330 nm、发射波长为420 nm;进样体积5μL。结果:在40%~160%的目标上样量范围内,峰面积与蛋白浓度呈良好线性(r>0.99);3个浓度水平下平均回收率分别为106.25%、100.00%、106.67%;定量限为0.03%。结论:该方法可用于不同糖蛋白药物中N-糖谱唾液酸化水平的检测。 展开更多
关键词 离子交换色谱 高唾液酸n糖谱 糖蛋白药物
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Effect of nutrient level on phytoplankton community structure in different water bodies 被引量:28
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作者 Wei Zhu Lei Wan Lianfang Zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期32-39,共8页
Increasing levels of pollution within water bodies can cause eutrophication and an associated rapid growth in and reproduction of phytoplankton. Although most frequently occurring in bodies of water such as lakes and ... Increasing levels of pollution within water bodies can cause eutrophication and an associated rapid growth in and reproduction of phytoplankton. Although most frequently occurring in bodies of water such as lakes and dams, in recent years an increasing number of river systems in China have suffered serious algal blooms. The community structure of phytoplankton may differ, however, dependent on the hydrodynamic conditions and nutrient levels within the water body. The field investigation results obtained from a stagnant river in Suzhou City and Taihu Lake, China, showed that in water with higher concentrations of nitrogen and phosphorus, Chlorophyta became the predominant species and in water with lower concentrations of nitrogen and phosphorus, Cyanobacteria became the predominant species. Growth experiments with competitive species, Microcystis aeruginosa Kutz and Scenedesmus quadricauda (Turp.), were conducted at three different nutrient levels. The biomass of algae in pure and mixed cultures was measured under conditions of different N/P ratios at oligotrophic, eutrophic and hypertrophic nutrient levels. The results indicated that the most suitable state for the growth and reproduction of M. aeruginosa and S. quadricauda were eutrophic conditions in both pure and mixed cultures. Under competition, however, the lower medium nutrient levels favoured M. aeruginosa, while the higher medium nutrient levels better suited S. quadricauda. Under similar hydrodynamic conditions, the community structure of phytoplankton in the water body was determined by the dominant species in competition for nutrients. 展开更多
关键词 PHYTOPLAnKTOn community structure nutrients level n/P ratio
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带有负顾客和N-策略的Geo/Geo/1排队模型均衡策略分析 被引量:1
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作者 张恒 刘力维 《应用数学》 北大核心 2024年第2期289-302,共14页
本文提出带有负顾客、N-策略休假和待机时间的Geo/Geo/1迟到达排队模型,并研究了此模型下的稳态条件、不同信息水平下顾客的策略和系统吞吐量的优化问题.负顾客到达发生在服务台在线阶段,其到达会抵消一个正在被服务的正顾客,即清除队... 本文提出带有负顾客、N-策略休假和待机时间的Geo/Geo/1迟到达排队模型,并研究了此模型下的稳态条件、不同信息水平下顾客的策略和系统吞吐量的优化问题.负顾客到达发生在服务台在线阶段,其到达会抵消一个正在被服务的正顾客,即清除队列头部的顾客(RCH).为此,系统设置了N-策略休假机制,即系统处于休假时,服务台不提供服务,此时负顾客也不会到达系统;直到顾客数目累积至N时,休假自动结束,服务台开始运行并按FCFS原则提供服务.系统一旦变空,会有一段待机时间,待机结束后,服务台关闭并进入休假.模型借助N-策略设置避免了频繁启动和关闭服务台造成的损耗,同时削弱了负顾客对系统产生的不良影响.分析得到了顾客在不同信息水平下的策略行为,同时给予系统管理者对于N-策略和信息展示水平的选择参考.最后通过数值模拟,验证了N-策略的保护作用和系统性能指标的敏感性. 展开更多
关键词 n-策略 负顾客 吞吐量 信息水平
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利用Level-Set函数求解的含表面张力项的N-S方程
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作者 高玉丽 《莱阳农学院学报》 2003年第2期125-127,共3页
流体的温度或组成的变化,都会引起表面张力的变化。因而在研究有关自由面的流体运动中,都要考虑自由面上的表面张力。本文利用当前流行的求解自由面的LevelSet方法给出含表面张力的N-S方程的推导。
关键词 表面张力 自由面 流体运动 level-Set函数 n-S方程 曲率
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Stark and Kerr Effects on the Dynamics of Moving N-Level Atomic System
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作者 Syed Jamal Anwar Mohammed Ramzan +1 位作者 Mohammed Usman Mohammed Khalid Khan 《Journal of Quantum Information Science》 2019年第1期22-40,共19页
We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linea... We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linear medium) and Stark effects. It is observed that the Stark and Kerr effects play a prominent role during the time evolution of the quantum system. The evolving quantum Fisher information (QFI) is noted as time grows under the non-linear Kerr medium contrary to the QE for higher dimensional systems. The effect of non-linear Kerr medium is greater on the QE as we increase the value of Kerr parameter. However, QFI and QE maintain their periodic nature under atomic motion. On the other hand, linear Kerr medium has no prominent effects on the dynamics of N-level atomic system. Furthermore, it has been observed that QFI and QE decay soon under the influence of Stark effect. In short, the N-level atomic system is found prone to the change of the Kerr medium and Stark effect for higher dimensional systems. 展开更多
关键词 QFI KERR EFFECT STARK EFFECT n-level ATOMIC System
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the phase-dependent gain without inversion in a Doppler broadened open four-level system
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作者 刘中波 贾克宁 +2 位作者 梁颖 仝殿民 樊锡君 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期227-233,共7页
It is shown that in a Doppler broadened open N-type four-level atomic system with spontaneously generated coherence (SGC), the gain without inversion (GWI) is very sensitive to the variation of the relative phase ... It is shown that in a Doppler broadened open N-type four-level atomic system with spontaneously generated coherence (SGC), the gain without inversion (GWI) is very sensitive to the variation of the relative phase between the probe field and the driving field; the atomic exit rate (R0) and the ratio (S) of the atomic injection rates have a considerable modulation effect on the phase-dependent GWI. GWI first increases and then decreases with R0 increasing; in a certain value range of S, GWI increases monotonically with S increasing; by adjusting the values of R0 and S, in an open system a much larger GWI can be obtained than in the corresponding closed system [2011 Phys. Rev. A 83 043805]. The modulation effects of R0 and S on the phase-dependent GWI in the case with the counter-propagating probe and driving fields are stronger than those in the co-propagating case, GWI in the co-propagating case is much larger than that in the counter-propagating case. 展开更多
关键词 open n-type four-level system spontaneously generated coherence relative phase Doppler broadening gain without inversion
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CTCS-N等级转换场景形式化建模与验证 被引量:1
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作者 高卓凡 何涛 +1 位作者 姜飞 吴永成 《兰州交通大学学报》 CAS 2024年第1期73-82,共10页
新型列车控制系统的车载设备承担更多地面设备的功能,其功能测试主要是以现场测试为主,费时费力,构建满足系统功能与性能需求的模型有助于保证列车在线路上安全、高效地运行,因此针对新型列控系统提出一种基于时间自动机的形式化建模与... 新型列车控制系统的车载设备承担更多地面设备的功能,其功能测试主要是以现场测试为主,费时费力,构建满足系统功能与性能需求的模型有助于保证列车在线路上安全、高效地运行,因此针对新型列控系统提出一种基于时间自动机的形式化建模与验证的方法。首先,选取等级转换场景为主要建模场景,提取规范中的功能与性能需求,梳理信息交互图,基于UPPAAL建立车载设备、应答器、临时限速服务器、无线闭塞中心的时间自动机模型;然后,使用模拟器进行模型的仿真,生成对应的消息顺序图;最后,以自动机语言为基础,验证正常模式和故障模式下车载设备转换是否满足要求。验证结果表明:所建立的模型满足等级转换场景的需求,其功能符合对应的技术规范,证明了该形式化建模的可行性,为新型列控系统测试、其他场景或功能的建模与验证提供了参考。 展开更多
关键词 新型列控系统 时间自动机 等级转换场景 建模与验证 消息顺序图
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The Pancharatnam Phase of a Three-Level Atom Coupled to Two Systems of N-Two Level Atoms
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作者 D. A. M. Abo-Kahla 《Journal of Quantum Information Science》 2016年第1期44-55,共12页
In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling param... In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling parameters between spins on the Pancharatnam phase and the atomic inversion, for some special cases of the initial states, are investigated. The comparison between the two effects shows that the analytic results are well consistent. 展开更多
关键词 Pancharatnam Phase Atomic Inversion Systems of n-Two level Atoms
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A Bit-level Text Compression Scheme Based on the ACW Algorithm
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作者 Hussein Al-Bahadili Shakir M. Hussain 《International Journal of Automation and computing》 EI 2010年第1期123-131,共9页
This paper presents a description and performance evaluation of a new bit-level, lossless, adaptive, and asymmetric data compression scheme that is based on the adaptive character wordlength (ACW(n)) algorithm. Th... This paper presents a description and performance evaluation of a new bit-level, lossless, adaptive, and asymmetric data compression scheme that is based on the adaptive character wordlength (ACW(n)) algorithm. The proposed scheme enhances the compression ratio of the ACW(n) algorithm by dividing the binary sequence into a number of subsequences (s), each of them satisfying the condition that the number of decimal values (d) of the n-bit length characters is equal to or less than 256. Therefore, the new scheme is referred to as ACW(n, s), where n is the adaptive character wordlength and s is the number of subsequences. The new scheme was used to compress a number of text files from standard corpora. The obtained results demonstrate that the ACW(n, s) scheme achieves higher compression ratio than many widely used compression algorithms and it achieves a competitive performance compared to state-of-the-art compression tools. 展开更多
关键词 Data compression bit-level text compression ACW(n algorithm Huffman coding adaptive coding
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中国欠发达县域的空间识别及其发展路径 被引量:4
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作者 刘彦随 杨林朋 郭远智 《地理科学》 北大核心 2025年第2期239-253,共15页
欠发达地区是不平衡、不充分发展的重要体现,也是推进中国式现代化面临的突出短板。本研究基于欠发达地区的科学认知,识别了中国欠发达县域的空间分布及其地域类型,提出了欠发达县域的发展路径,以期为建立健全欠发达地区常态化帮扶机制... 欠发达地区是不平衡、不充分发展的重要体现,也是推进中国式现代化面临的突出短板。本研究基于欠发达地区的科学认知,识别了中国欠发达县域的空间分布及其地域类型,提出了欠发达县域的发展路径,以期为建立健全欠发达地区常态化帮扶机制提供参考。研究发现:(1)作为人地关系负向演化的结果,欠发达地区是一个以经济欠发达为主要内容的相对地理概念,由此决定了对欠发达地区的识别宜采取“1+N”的方案。(2) 2022年,全国县域经济发展水平高值区主要分布在内蒙古和新疆的边境地区以及苏-浙-闽沿海地区,其背后的主导因素包括交通运输用地占比、受教育年限、城镇化率和第一产业增加值占比。(3)基于主导因素识别的部门欠发达县域包括交通欠发达县域、教育欠发达县域、城镇化欠发达县域和工业化欠发达县域,宜采取针对性措施补短板、强弱项。(4)经济欠发达县域主要分布在原集中连片特殊困难地区,可依据县域经济发展水平的主导制约因素将其划分为工业化和城镇化约束型经济欠发达县域、工业化约束型经济欠发达县域、教育和城镇化约束型经济欠发达县域、多要素相对约束型经济欠发达县域和多要素严格约束型经济欠发达县域5类,不同类型欠发达县域的常态化帮扶策略应立足其主导制约因素的组合,因地制宜、分类指导、分区实施。 展开更多
关键词 经济发展水平 “1+n”方案 经济欠发达县域 欠发达地区 乡村地域系统 人地系统科学
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基于ADACS_N平台的DCS二层系统服务器国产化替代与软件移植研究
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作者 黄鸿 《自动化应用》 2024年第10期279-281,284,共4页
针对核电厂DCS系统服务器硬件老化与停产共性问题,基于法国ADACS_N平台的DCS二层系统,研究一种服务器国产化替代与软件移植的可行方法,结合系统软硬件架构分析、国产化服务器硬件替代选型策略、源代码移植技术研究、最小化测试平台开发... 针对核电厂DCS系统服务器硬件老化与停产共性问题,基于法国ADACS_N平台的DCS二层系统,研究一种服务器国产化替代与软件移植的可行方法,结合系统软硬件架构分析、国产化服务器硬件替代选型策略、源代码移植技术研究、最小化测试平台开发,为延长核电厂DCS系统生命周期、解决进口设备“卡脖子”问题、提升核电厂DCS关键设备自主能力提供一定参考。 展开更多
关键词 核电厂 ADACS_n平台 DCS二层系统服务器 国产化替代 软件移植 源代码移植
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Modulation of atomic exit and injection rates on the phase-dependent gain without inversion in a Doppler broadened open four-level system
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作者 刘中波 贾克宁 +2 位作者 梁颖 仝殿民 樊锡君 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期231-237,共1页
It is shown that in a Doppler broadened open N-type four-level atomic system with spontaneously generated coherence (SGC), the gain without inversion (GWI) is very sensitive to the variation of the relative phase betw... It is shown that in a Doppler broadened open N-type four-level atomic system with spontaneously generated coherence (SGC), the gain without inversion (GWI) is very sensitive to the variation of the relative phase between the probe field and the driving field; the atomic exit rate (R0) and the ratio (S) of the atomic injection rates have a considerable modulation effect on the phase-dependent GWI. GWI first increases and then decreases with R0 increasing; in a certain value range of S, GWI increases monotonically with S increasing; by adjusting the values of R0 and S, in an open system a much larger GWI can be obtained than in the corresponding closed system [2011 Phys. Rev. A 83 043805]. The modulation effects of R0 and S on the phase-dependent GWI in the case with the counter-propagating probe and driving fields are stronger than those in the co-propagating case, GWI in the co-propagating case is much larger than that in the counter-propagating case. 展开更多
关键词 open n-type four-level system spontaneously generated coherence relative phase Doppler broadening gain without inversion
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