检索结果-南通市图书馆

Asymptotic Behavior of Global Classical Solutions of Quasilinear Non-strictly Hyperbolic Systems with Weakly Linear Degeneracy

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2006年第3期27卷 263-286页

作者： Wenrong dai Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China.

In this paper, we study the asymptotic behavior of global classical solutions of the Cauchy problem for general quasilinear hyperbolic systems with constant multiple and weakly linearly degenerate characteristic fields. Based on the existence of global classical solution proved by Zhou Yi et al., we show that, when t tends to infinity, the solution approaches a combination of C^1 travelling wave solutions, provided that the total variation and the L^1 norm of initial data are sufficiently small.

关键词： Asymptotic behavior Characteristic fields with constant multiplicity,Weakly linear degeneracy Global classical solution Normalized coordinates Travelling wave

Calibration method of phase distortions for cross polarization channel of instantaneous polarization radar system

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2010年第2期21卷 211-218页

作者： Huanyao dai Yuliang Chang Dahai dai Yongzhen Li XuesongWang School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 R R. China

A novel polarimetric calibration method for new target property measurement radar system is presented. Its applica- tion in the real radar system is also discussed. The analysis indicates that instantaneous polarization radar （[PR） has inherent cross-polarization measurement error. The proposed method can effectively eliminate this error, and thus enhance the polarization scattering matrix （PSM） measurement precision. The phase error caused by digital receiver＇s direct IF sampling and mixing of two orthogonal polarization channels can be removed. Consequently, the inherent error of target polarization scattering measurement of the instantaneous polarization radar system is well revised. It has good reference value for further ploarimetric calibration and high practical application prospect.

关键词： instantaneous polarization radar target scattering ma- trix (PSM) polarization measurement polarimetric calibration.

Kinetics of testosterone recovery in clinically localized prostate cancer patients *** radical prostatectomy and subsequent short-term adjuvant androgen deprivation therapy

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2013年第4期15卷 466-470,I0006页

作者： Bo dai Department of Urology Fudan University Shanghai Cancer Center Shanghai 200032 China Department of Oncology Fudan University Shanghai Medical College Shanghai 200032 China and Department of Pathology Fudan University Shanghai Cancer Center Shanghai 200032 China

deprivation therapy （ADT） is a standard treatment for metastatic, recurrent and locally advanced prostate cancer （PCa）. The aim of this study is to investigate the timing and extent of testosterone recovery in clinically localized PCa patients treated with radical prostatectomy （RP） and subsequent short-term adjuvant ADT. A total of 95 localized PCa patients underwent RP and 9-month adjuvant ADT were included in this prospective study. Serum testosterone level was measured before adjuvant ADT, at ADT cessation, and at 1, 3, 6, 9 and 12 months after cessation of ADT. A Cox proportional hazards model was used to assess variables associated with the ti me of testosterone normalization. The results showed that median patient age was 67 years and median testosterone level before adjuvant ADT was 361 （230-905） ng d1-1. All patients finished 9-month adjuvant ADT and achieved castrate testosterone level. At 3 months after ADT cessation, testosterone recovered to supracastrate level in 97.9% patients and to normal level in 36.9% patients. The percentage of patients who recovered to normal testosterone level increased to 66.3%, 86.3% and 92.6% at 6, 9 and 12 months, respectively. Cox regression model found that higher baseline testosterone level （ 300 ng dl- 1） was the only variable associated with a shorter time to testosterone normalization （hazard ratio： 1.98; P -- 0.012）. In conclusion, in most patients, testosterone recovered to supracastrate level at 3 months and to normal level at 12 months after 9-month adjuvant ADT cessation. Patients with higher baseline testosterone level need shorter time of testosterone normalization.

关键词： androgen deprivation therapy (ADT) luteinizing hormone-releasing hormone prostatic neoplasms recovery of function testosterone

浙江缙云壶镇盆地一带沸石矿石矿物特征及物化性能分析

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

矿物岩石 2007年第1期27卷 23-29页

作者：刘伟刘纯波张术根戴塔根傅文杰中南大学地学与环境工程学院湖南长沙410083 中南大学材料科学与工程学院湖南长沙410083 西部矿业博士后科研工作站青海西宁810001

运用X射线衍射、扫描电镜形貌研究及微区化学成分分析等手段,对浙江省缙云县壶镇盆地及其外围沸石矿床沸石进行系统研究,确定其矿物组成主要为斜发沸石和丝光沸石,二者可单独产出,也可形成混合型矿石。研究区矿石在成分上属高硅型沸石,S... 详细信息

运用X射线衍射、扫描电镜形貌研究及微区化学成分分析等手段,对浙江省缙云县壶镇盆地及其外围沸石矿床沸石进行系统研究,确定其矿物组成主要为斜发沸石和丝光沸石,二者可单独产出,也可形成混合型矿石。研究区矿石在成分上属高硅型沸石,SiO2/Al2O3比值接近于8,有害元素Fe,Mn,Ti等质量分数很低。物化性能测试表明,浙江省缙云县壶镇盆地及其外围沸石矿为高品级沸石矿,矿石NH4+交换容量为163 mmol/100 g～212 mmol/100 g,K+交换容量为15.73×10-3～19.30×10-3,氮气吸附能力为13.1 ml/g～21.0 ml/g,比表面积测试值为157.17 m2/g～191.50 m2/g,具有良好的开发应用前景。

关键词：斜发沸石丝光沸石矿物特征物化性能浙江缙云

Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2024年第1期23卷 163-178页

作者： Wu Houli Guo Endong Wang Jingyi dai Xin dai Chenxi Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China

As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much *** paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame *** material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic *** response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical *** acceleration response and displacement response of different combinations are *** results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes.

关键词： water supply pipe different materials shaking table test amplification factor seismic fragility

Morpho-physiological traits contributing to better yield performance of japonica/indica hybrids over indica hybrids under input-reduced practices

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2020年第11期19卷 2643-2655页

作者： WEI Huan-he MENG Tian-yao GE Jia-lin ZHANG Xu-bin LU Yu LI Xin-yue taO Yuan DING Enhao CHEN Ying-long dai Qi-gen Jiangsu Key Laboratory of Crop genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops/Research Institute of Rice Industrial Engineering Technology Yangzhou UniversityYangzhou 225009P.R.China Institute of Agricultural Science and Technology Development Yangzhou University/Joint International Research Laboratory of Agriculture and Agri-Product SafetyMinistry of EducationYangzhou 225009P.R.China

It is widely reported that japonica/indica hybrids(JIH)have superior grain yield over other main varietal groups such as indica hybrids(IH)under sufficient resource *** date,little attention has been paid to yield performance of JIH under input-reduced practices,and whether JIH could have better grain yield performance over IH under input-reduced *** this study,three JIH varieties and three IH varieties were compared in grain yield and their related morpho-physiological traits under two cultivation modes,i.e.,conventional high-yielding method(CHYM)and double reductions in nitrogen rate and planting density(DRNP).Our results showed that JIH had 8.3 and 13.3%higher grain yield over IH under CHYM and DRNP,*** superior grain yield of JIH over IH under DRNP was mainly attributed to larger sink size and improved sink filling *** main morpho-physiological traits were concluded for better yield performance of JIH over IH under ***,JIH had the reduced unproductive tillers growth,indicated by a higher percentage of productive tillers and the percentage of effective leaf area index(LAI)to total LAI at heading ***,a synergistic increase in biomass accumulation and harvest index were achieved of JIH,supported by higher biomass accumulation and leaf area duration during the main growth periods,and improved non-structural carbohydrate(NSC)remobilization after ***,JIH had an improved canopy structure,showing as higher leaf area of upper three leaves and lower light extinction *** results suggested that improved morpho-physiological traits of JIH could lead to better grain yield performance over IH under input-reduced practices.

关键词： japonica/indica hybrid rice grain yield input-reduced practices

Heavy Traffic Limit Theorems for a Queue with Poisson ON/OFF Long-range Dependent Sources and general Service Time Distribution

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2012年第4期28卷 807-822页

作者： Wan-yang dai Department of Mathematics and State Key Laboratory of Novel Software TechnologyNanjing University

In Internet environment, traffic flow to a link is typically modeled by superposition of ON/OFF based sources. During each ON-period for a particular source, packets arrive according to a Poisson process and packet sizes （hence service times） can be generally distributed. In this paper, we establish heavy traffic limit theorems to provide suitable approximations for the system under first-in first-out （FIFO） and work-conserving service discipline, which state that, when the lengths of both ON- and OFF-periods are lightly tailed, the sequences of the scaled queue length and workload processes converge weakly to short-range dependent reflecting Gaussian processes, and when the lengths of ON- and/or OFF-periods are heavily tailed with infinite variance, the sequences converge weakly to either reflecting fractional Brownian motions （FBMs） or certain type of long- range dependent reflecting Gaussian processes depending on the choice of scaling as the number of superposed sources tends to infinity. Moreover, the sequences exhibit a state space collapse-like property when the number of sources is large enough, which is a kind of extension of the well-known Little＇s law for M/M/1 queueing system. Theory to justify the approximations is based on appropriate heavy traffic conditions which essentially mean that the service rate closely approaches the arrival rate when the number of input sources tends to infinity.

关键词： reflecting fractional Brownian motion reflecting Gaussian process long-range dependence queueing process weak convergence

准噶尔北缘典型金矿床的稀土元素地球化学特征

在线全文

学校读者我要写书评

暂无评论

中南工业大学学报 2000年第5期31卷 379-383页

作者：廖启林戴塔根刘悟辉中南大学资源环境与建筑工程学院湖南长沙410083

准噶尔北缘存在浅成低温热液型金矿床、韧性剪切带蚀变糜棱岩型金矿床及浅成岩构造蚀变岩型金矿床等主要矿化类型 .通过分析比较这些主要矿化类型金矿的REE资料 ,建立了各典型金矿床的REE配分模式 ,探讨了各矿化类型金矿床之间的REE地... 详细信息

准噶尔北缘存在浅成低温热液型金矿床、韧性剪切带蚀变糜棱岩型金矿床及浅成岩构造蚀变岩型金矿床等主要矿化类型 .通过分析比较这些主要矿化类型金矿的REE资料 ,建立了各典型金矿床的REE配分模式 ,探讨了各矿化类型金矿床之间的REE地球化学行为差异及其与成矿的关系 .结果表明 ,就成矿作用而言 ,浅成岩构造蚀变岩型金矿床比较简单 ,韧性剪切带蚀变糜棱岩型金矿床较复杂。

关键词：金矿床稀土元素地球化学特征准噶尔北缘矿化

Cerebral glucose metabolic prediction from amnestic mild cognitive impairment to Alzheimer’s dementia:a meta-analysis

在线全文

学校读者我要写书评

暂无评论

Translational Neurodegeneration 2018年第1期7卷 81-90页

作者： Hai Rong Ma Li Qin Sheng Ping Lei Pan gen Di Wang Rong Luo Hai Cun Shi Zhen Yu dai Jian Guo Zhong Department of Neurology Traditional Chinese Medicine Hospital of KunshanKunshanPeople’s Republic of China Department of Neurology School of MedicineAffiliated Yancheng HospitalSoutheast UniversityWest Xindu Road 2#YanchengJiangsu Province 224001People’s Republic of China Department of Radiology School of MedicineAffiliated Yancheng HospitalSoutheast UniversityWest Xindu Road 2#YanchengJiangsu Province 224001People’s Republic of China

Brain 18F-fluorodeoxyglucose positron emission tomography(FDG-PET)has been utilized to monitor disease conversion from amnestic mild cognitive impairment(aMCI)to Alzheimer’s dementia(AD).However,the conversion patterns of FDG-PET metabolism across studies are not *** conducted a voxel-wise meta-analysis using Seed-based d Mapping that included 10 baseline voxel-wise FDG-PET comparisons between 93 aMCI converters and 129 aMCI nonconverters from nine longitudinal *** most robust and reliable metabolic alterations that predicted conversion from aMCI to AD were localized in the left posterior cingulate cortex(PCC)/***,meta-regression analyses indicated that baseline mean age and severity of cognitive impairment,and follow-up duration were significant moderators for metabolic alterations in aMCI *** study revealed hypometabolism in the left PCC/precuneus as an early feature in the development of *** finding has important implications in understanding the neural substrates for AD conversion and could serve as a potential imaging biomarker for early detection of AD as well as for tracking disease progression at the predementia stage.

关键词： Alzheimer’s dementia Mild cognitive impairment FDG-PET Conversion Meta-analysis Seed-based d mapping