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Search Results: 1 - 10 of 276001 matches for " 李思慧? "
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基于LMD-PSO-LSSVM组合模型的深基坑变形预测
Deep Foundation Pit Deformation Prediction Based on LMD-PSO-LSSVM Model

,刘海卿
- , 2018,
Abstract: 摘要 变形是造成基坑安全隐患的重要因素。为准确预测基坑变形趋势,提出一种将局部均值分解(LMD)、粒子群优化算法(PSO)与最小二乘支持向量机(LSSVM)组合的深基坑变形预测模型。通过 LMD 将时序样本分解为多个分量,利用PSO优化后的LSSVM模型对各分量建立非线性基坑变形预测模型,最后采用滚动预测的方法对各分量进行预测并将结果叠加得到时序样本的预测值。通过实际工程进行模型预测与分析。结果表明:该模型不仅反映出基坑变形本质特征,而且预测精度明显提高,将其运用于基坑变形预测研究中具有较好的应用性和可靠性。
热转移印刷中承印物热力学性能的研究
,钱军浩
包装工程 , 2013,
Abstract: 热转移印刷中温度及压力是影响印刷质量的关键因素,通过对热转移印刷中承印物的热力学性能研究,分析了承印物在高温条件下的蠕变曲线,以及热转移印刷中转印温度、转印时间及印刷压力对热转移印刷质量的影响,为实际印刷操作中转印温度的控制,转印时间及印刷压力的确定提供理论依据。
复杂网络中的弱化免疫策略分析
,嘉*,赵岳
计算机应用 , 2012,
Abstract: ?针对免疫策略在病毒免疫时会删除网络结构级联边从而出现削弱网络连通效率的问题,提出一种含权网络特定的病毒弱化免疫策略方法。该方法通过构建si病毒传播模型,给出该模型的病毒感染密度演化公式。理论分析表明:病毒传播率与网络结构的异化性有密切关系,节点度的大小会影响病毒传播的效果,同时弱化免疫策略能衰减连边权值降低传播率,达到遏制病毒传播保留网络连通效率的目的。计算机仿真结果验证了理论模型的可行性和弱化免疫的合理性。最后,将弱化免疫策略应用到局域世界以及目标免疫策略中,更进一步说明了弱化免疫策略能有效控制病毒传播速度。
一种快速有效分析烟草花冠中花青素苷的方法
孙翊, , 王亮生,
植物学报 , 2011, DOI: 10.3724/SP.J.1259.2011.00189
Abstract: ?花青素苷(anthocyanins)成分和含量的分析是花色研究的重要内容之一。该文利用高效液相色谱-电喷雾离子化-质谱技术(HPLC-ESI-MS),建立了一种快速有效地分析烟草(Nicotianatabacum)花冠中花青素苷成分及含量的方法。在保证良好分离效果的基础上,将分析时间缩短至15分钟,大大提高了分析速度,降低了成本,并成功应用于转基因烟草花冠中花青素苷成分的分析。为不具备高效分析仪器(如超高效液相色谱-串联质谱(UPLC-MS/MS))的一般实验室研究花青素苷合成相关基因在烟草中的异源表达提供了一种有效且实用的分析方法。
高粱杂种后代(F1F2)早熟性、品质及株性高状的控制
陆锦池,,金福
华北农学报 , 1982, DOI: 10.7668/hbnxb.1982.03.025
Abstract: 选育早熟、优质高梁杂交种,是当前高梁生产和科研的发展趋向。本研究试图从高梁杂种后代(F1F2)早熟性、品质及其株高性状的分析,作为改进试验设计和正确选择亲本,提高选择效果的参考。一、早熟性况的控制:1977年杂交,1978、1979年分别观察了F1代杂种及其亲本28个组合,重点分析了F2代的分离特点,早熟性用抽穗期作标志,达到70%则为抽穗期,分为早、中、晚熟三种类型。
保鲜运输用管道式加湿装置的设计与试验
Design and experiment of pipeline humidifying device for fresh-keeping transportation

,郭嘉明,,
- , 2015,
Abstract: 【目的】研究厢内管道式超声波加湿装置的工作特性,提高保鲜运输加湿系统的工作性能,改善保鲜环境的湿度均匀性。【方法】设计了一套管道式加湿装置,搭建保鲜运输加湿系统试验平台并研究水雾输送管管径(12.5,19.0和25.4 mm)、开孔数(2,4,6和8孔)、水雾输送风机电压(12,18和24 V)、回风道风速(4,6和8 m/s)对加湿特性的影响。【结果】水雾输送管管径、回风道风速、水雾输送管开孔数、水雾输送风机电压对加湿均匀性的影响程度依次减小;在水雾输送管管径为25.4 mm、回风道风速为4 m/s、水雾输送管开孔数为4孔、水雾输送风机电压为24 V时,厢内相对湿度标准差最低,为2.92;在回风道风速为8 m/s、水雾输送风机电压为24 V、水雾输送管开孔数为8孔、水雾输送管管径为25.4 mm时,加湿速率最高,加湿时间为372 s。【结论】综合考虑确定水雾输送管管径25.4 mm、回风道风速4 m/s、水雾输送管开孔数4孔、水雾输送风机电压24 V为保鲜运输用管道式加湿装置的最优参数组合。
【Objective】This study investigated the operating characteristics of pipeline humidifying device to improve the performance of humidification system and the humidity uniformity of preservation environment.【Method】A pipeline humidifying device was designed and experimental platform for fresh keeping transportation humidification system was established.The effects of pipe diameter (12.5,19.0 and 25.4 mm), number of holes (2,4,6 and 8),voltage of fan (12,18 and 24 V),and speed of air duct(4,6 and 8 m/s) on the wetting characteristics were also analyzed.【Result】The effects of pipe diameter,number of holes,voltage of fan,and speed of air duct on humidity uniformity were in the order of pipe diameter>number of holes>voltage of fan>speed of air duct.When pipe diameter was 25.4 mm,speed of air duct was 4 m/s,number of holes was 4,and voltage of fan was 24 V,the lowest value of humidification uniformity of 2.92 was obtained.The highest humidifying rate was obtained when speed of air duct was 8 m/s,voltage of fan was 24 V,number of holes was 8,pipe diameter was 25.4 mm and humidifying time was 372 s.【Conclusion】Based on comprehensive consideration,optimal parameters of pipeline humidifying device for fresh-keeping transportation were:pipe diameter 25.4 mm,speed of air duct 4 m/s,number of holes 4,and voltage of fan 24 V
基于色彩色差计和电子鼻的槟榔炒制火候判别及其指标量化研究
黄学,文敏,张小琳,贾晶,,吴纯洁
中国中药杂志 , 2009,
Abstract: 目的:引进色彩色差计和电子鼻,将经验指标数据化,实现槟榔炒制“火候”判别的客观数量化,为研究中药炮制共性技术问题提供一种新的方法及思路。方法:以槟榔为研究对象,在全国范围内采集槟榔及炮制品,应用色彩色差计和电子鼻采集其颜色特征参数和气味特征参数,通过统计分析总结炮制经验,建立“火候”判别的数学预测模型和90%参考值范围。结果:建立了基于L*a*b*色度空间的槟榔炒制火候判断的数学判别模型,其判别符合率为100%,双侧90%参考值范围分别为生品:L*(50.07~55.03),a*(4.136~6.906),b*(6.65~8.82);炒品:L*(43.874~47.998),a*(3.816~6.732),b*(3.786~6.558);焦品:L*(38.744~40.616),a*(1.11~3.01),b*(-1.434~0.538);电子鼻采集不同炮制品的气味数据,通过线性判别分析(LAD)和主成分分析(PCA),证明不同炮制程度的槟榔气味存在显著区别,建立了数学判别模型。结论:通过实验证明色彩色差计和电子鼻均可区分不同炮制程度的槟榔样品,采用色彩色差计和电子鼻判别中药炮制的“火候”,具有一定的可行性,对深入研究中药传统理论提供了参考。
妊娠期肾绞痛的诊疗分析
陈长青,,龚旻,顾建军,
- , 2015, DOI: 10.16118/j.1008-0392.2015.06.012
Abstract: 目的 提高妊娠期肾绞痛的诊断与治疗水平。方法 结合国内外文献,对48例首诊为妊娠期肾绞痛患者的临床资料进行回顾性分析。结果 B超发现肾积水伴输尿管结石21例,其中1例双侧输尿管结石;B超发现肾积水但未发现输尿管结石27例,其中1例首诊误诊为妊娠期肾绞痛,妊娠晚期剖宫产证实为右卵巢畸胎瘤不完全蒂扭转并卵巢部分坏死行卵巢部分切除术。35例行保守治疗有效;1例肾积水进展者、1例双输尿管结石伴双肾积水者、1例肾积脓者及9例顽固性肾绞痛者行Double J(D-J)管置入术;1例重度肾积水者行经皮肾造瘘(Percutaneous Nephrostomy, PCN)术。47例安全顺利分娩或剖宫产,1例早产。结论 妊娠期肾绞痛的诊断具有挑战性,须严格排除其他急腹症。保守治疗对大部分患者有效,但需随访肾积水进展;保守治疗无效时,D-J管置入术是一种安全、简单、有效的治疗方法。
Objective To review the diagnosis and treatment of renal colic during pregnancy. Methods The clinical data of 48 women who were diagnosed as renal colic during pregnancy in the first visit were retrospectively analyzed and relevant literature was reviewed. Result B-ultras-onography detected that 21 cases had hydronephrosis with ureteral stones including bilateral ureteral stones in 1 case, and 27 cases had hydronephrosis without ureteral stones. One patient with right ovarian teratoma torsion was misdiagnosed as renal colic in the first visit, and underwent partial ovariectomy after diagnosis confirmed. Thirty five cases adopted conservative treatment with satisfactory outcomes. Among remaining 13 cases, 1 case of progressing hydronephrosis, 1 case of bi-lateral ureteral stones and bilateral hydronephrosis, 1 case of pyonephrosis and 9 cases of refractory renal colic received D-J stent placement; 1 case with severe hydronephrosis received percutaneous nephrostomy (PCN). Forty seven cases underwent normal delivery or cesarean section, and 1 case had premature delivery. Conclusion Conservative management is effective in the majority of patients with renal colic during pregnancy, for patients with conservation failure placement of D-J stent is recommended
基于小波变换的沪深300指数预测
Hushen 300 Index Price Forecasting Based on Wavelet Transform
 [PDF]

, 费宇
Statistics and Applications (SA) , 2014, DOI: 10.12677/SA.2014.34024
Abstract:
本文通过基于小波变换和未基于小波变换对沪深300指数日收盘价序列分别建立ARMA拟合模型并做短期预测,对其归一化均方误差(NMSE)进行比较,结果显示,由于小波变换良好的时频局域化特性,以及它的多分辨功能,使组合模型较之于单个预测模型对于沪深300指数的短期预测更优。
This paper based on wavelet transform and non-wavelet transform established ARMA models to fit the daily closing price of Shanghai and Shenzhen 300 index and do a short-term forecast. It also compared their normalized mean square error (NMSE). Results display that due to the characte-ristics of wavelet transform which are good time frequency localization and its multi-resolution features, combined forecast model for short-term forecast of Shanghai and Shenzhen 300 index is superior to single forecast model.
慢性间歇性低压低氧对大鼠离体肺动脉环舒张功能的影响*
Effects of chronic intermittent hypobaric hypoxia on pulmonary vasodilatation of rats

,,,王立轩,,,王亚萍,
- , 2016,
Abstract: 目的:探讨慢性间歇性低压低氧(CIHH)对大鼠离体肺动脉环舒张功能的影响及其机制。方法:成年雄性SD大鼠随机分为对照组、CIHH组、对照+阻断剂组和CIHH+阻断剂组。CIHH大鼠给予每天6 h模拟海拔5 000 m的低压低氧处理,对照置于常压常氧环境同期饲养,28 d后处死大鼠,制备肺动脉环,加阻断剂组给予终浓度为10 μmol/L MEK特异性阻断剂PD98059或PI3K阻断剂LY294002处理20 min。采用灌流实验记录乙酰胆碱诱导的肺动脉的舒张活动; 应用Western blot法检测肺动脉组织中eNOS的表达水平。结果:CIHH处理可增强乙酰胆碱引起的肺动脉舒张,提高肺动脉组织中eNOS的表达(P<0.05); PD98059共孵育对CIHH的作用无影响(P>0.05),LY294002共孵育可部分阻断CIHH的作用(P<0.05)。结论:CIHH处理可能通过PI3K途径活化血管内皮eNOS,增强乙酰胆碱诱导的大鼠肺动脉舒张。
Aim: To investigate the effects of chronic intermittent hypobaric hypoxia(CIHH)on the vasodilatation of isolated pulmonary artery in rats and the underlying mechanism.Methods: Adult male SD rats were randomly allocated into 4 groups: control group, CIHH group, control+blocking agent group and CIHH+blocking agent group.The rats in CIHH groups were exposed to hypoxia simulating 5000 m high altitude in a hypobaric chamber for 28 d, 6 h each day. The rats in control group were maintained in a normoxic environment for a corresponding period. The rats in groups treated with blocking agent were given 10 μmol/L MEK inhibitor PD98059 or PI3K inhibitor LY294002 for 20 min.The vasodilatation of pulmonary artery was recorded by using organ bath technique. The protein expression level of eNOS in pulmonary artery tissue was measured by Western blot.Results: CIHH could remarkably augment the acetylcholine(ACh)induced vasodilatation of pulmonary artery and increase the expression of eNOS in pulmonary artery tissue(P<0.05). Incubated with PD98059 did not affect the effects of CIHH on pulmonary artery. Incubation of LY294002 blocked the effects of CIHH(P<0.05).Conclusion: The data demonstrate that CIHH treatment may enhance ACh induced vasodilatation of pulmonary artery by activating eNOS via PI3K pathway
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