Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families

In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞.

Eutrophication model for river-type reservoir tributaries and its applications

With the impoundment of the Three Gorges Reservoir, algal blooms have been found in some tributaries. In this study, according to the theoretical analysis of the eutrophication mechanism in a river-type reservoir tributary, a one-dimensional eutrophication model was developed for the Xiangxi River tributary of the Three Gorges Reservoir, and the influence of hydrodynamic conditions on the primary growth rate of algae was investigated. Furthermore, numerical predictions of hydraulic variables and eutrophication factors, such as the concentration distribution of TP, TN, and Chl-a in the spatial and temporal domains, were carried out. Comparison of computation results of TP, TN, and Chl-a concentrations along the river in the spring of 2005 with experimental data demonstrates the validity of the model. The agreement between the computation results and the experimental data of TP and TN concentrations is better than the agreement between those of Chl-a concentration. The simulated results also show that the Chl-a concentration downstream is much higher than that in the upstream tributary, which potentially indicates the outbreak of algae in this area. Therefore, this study provides a feasible method of accurately predicting the state of eutrophication in river-type reservoirs and their tributaries.

One-sided empirical Bayes test for location parameter in Gamma distribution

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.

An Efficient Second-Order Convergent Scheme for One-Side Space Fractional Diffusion Equations with Variable Coefficients

In this paper,a second-order fnite-diference scheme is investigated for time-dependent space fractional difusion equations with variable coefcients.In the presented scheme,the Crank-Nicolson temporal discretization and a second-order weighted-and-shifted Grünwald-Letnikov spatial discretization are employed.Theoretically,the unconditional stability and the second-order convergence in time and space of the proposed scheme are established under some conditions on the variable coefcients.Moreover,a Toeplitz preconditioner is proposed for linear systems arising from the proposed scheme.The condition number of the preconditioned matrix is proven to be bounded by a constant independent of the discretization step-sizes,so that the Krylov subspace solver for the preconditioned linear systems converges linearly.Numerical results are reported to show the convergence rate and the efciency of the proposed scheme.

An Analysis of Labor Resources “One River and Two Tributaries” Region in Tibet, China

Focusing on the region of Yarlung Zangbo River and the middle reaches of itstwo tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the 'One Riverand Two Tributaries' region), and based on the data from China 3rd, 4th and5th population censuses,the article has analyzed change patterns of this region' s labor force. Major findings from thestudy are summarized as follows; (1) Compared with the data from the 3rd census, labor forcepopulation in 2000 has increased significantly. (2) Children dependency coefficient has dropped,while old people dependency coefficient has changed very slightly with an increase of 0. 047% only.(3) Compared 2000 with 1982, illiteracy and semi-illiteracy rate of the population above 15 yearsold have decreased significantly by 30. 69 percentage points, but still higher than the nationalaverage. (4) Women' s illiteracy rate has dropped faster than men's, but up to 2000 it was generallyquite high. The upgrading of the entire population's overall quality has a long way to go.

Influence of tributaries on downstream bed sediment grain sizes under flysch conditions

Tributaries are one of the most important factors contributing to variability in the downstream evolution of bed sediment grain size.The primary aim of this work is to evaluate the response of the bed sediment texture in the recipient channel induced by ten tributaries of the?ernáOstravice stream and find reach-scale and catchment-scale parameters that would be able to predict this response.The research was based on collecting information on the grain size distributions at sites adjacent to confluence zones.A significant change in sediment texture occurred in the vicinity of five confluences.Considering the other factors contributing to grain size variability(e.g.,local channel geometry,lithology,and lateral sediment sources),it was assumed that only four of them were associated with a sufficient bedload influx to alter the sediment calibre below the junction.Moreover,a significant morphological effect in the form of a large confluence bar was observed in one case.These tributaries had several common features:(i)they had a larger relative catchment area than that of nonsignificant tributaries;(ii)they were characterized by different bed grain sizes,with some exceptions;and(iii)they had a higher unit stream power close to the confluence in relation to that of the mainstream.These characteristics were represented by the proposed relative parameters,including the relative unit stream power and bed material texture,which allowed the best classification of significant and nonsignificant tributaries.In their simplified form,the parameters described the transport capacity and grain size distribution,which were generally considered to be primary factors responsible for a redefinition of the sediment texture in the recipient channel.However,it should be noted that these results are subject to some degree of uncertainty due to the relatively small sample size of only 10 tributaries.

Tracking PCB Contamination in Ontario Great Lakes Tributaries: Development of Methodologies and Lessons Learned for Watershed Based Investigations

Project Trackdown is an investigative environmental program aimed at tracking sources of polychlorinated biphenyl (PCB) contamination in Great Lakes tributaries. The program uses a multimedia weight of evidence approach for identifying sources of PCBs to the environment. PCB concentrations in environmental media (sediment, water, suspended sediment and soil), passive samplers and/or exposed biota (mussels, young-of-the-year fish and benthic invertebrates) are used in combination to evaluate bioavailability and identify local anomalies within a tributary. These lines of evidence can be assessed with simple chemometric techniques and fingerprinting of PCB congener profiles, and, combined with anecdotal information such as land use history and tributary alterations, may be used to identify ongoing and locally controllable sources of PCBs to the Great Lakes. The program was successful at developing environmental triggers to differentiate potential source areas from background PCB conditions in urban areas, allowing efforts to focus on identifying active ongoing sources of PCB contamination. Project Trackdown has been carried out in three tributaries to Lake Ontario (Cataraqui River, Etobicoke Creek and Twelve Mile Creek) and two tributaries that flow into the Detroit River (Turkey Creek and Little River). Local ongoing PCB sources have been identified in four projects, leading to abatement or remediation measures. As a collaborative initiative between the Ontario Ministry of the Environment and Environment Canada, Project Trackdown has successfully identified several PCB sources leading to substantial cleanup efforts aimed ultimately at reducing PCB contamination to the Great Lakes.

The Best m-Term One-Sided Approximation of Besov Classes by the Trigonometric Polynomials

In this paper, we continue studying the so called best m-term one-sided approximation and Greedy-liked one-sided ap- proximation by the trigonometric polynomials. The asymptotic estimations of the best m-terms one-sided approximation by the trigonometric polynomials on some classes of Besov spaces in the metricLp(Td(1≤p≤∞ are given.

Variation Inequalities for the Commutators of One-Sided Calderón-Zygmund Singular Integrals with Lipschitz Functions

In this paper, we establish the weighted Lp (1 < p < ∞) boundedness of variation operator for the commutators generated by one-sided Calderón-Zygmund singular integrals with Lipschitz functions.

New Approach to Observer-Based Finite-Time H_(∞)Control of Discrete-Time One-Sided Lipschitz Systems with Uncertainties

This paper investigates the finite-time H_(∞)control problem for a class of nonlinear discrete-time one-sided Lipschitz systems with uncertainties.Using the one-sided Lipschitz and quadratically inner-bounded conditions,the authors derive less conservative criterion for the controller design and observer design.A new criterion is proposed to ensure the closed-loop system is finite-time bounded(FTB).The sufficient conditions are established to ensure the closed-loop system is H_(∞)finite-time bounded(H_(∞)FTB)in terms of matrix inequalities.The controller gains and observer gains are given.A numerical example is provided to demonstrate the effectiveness of the proposed results.

超标横流作用下航道尺度加宽研究及应用

支流入汇常导致支流口干流航道局部横流加大,进而影响船舶通航安全。为研究超标横流入汇对干流航道尺度的影响,采用Fortran语言自主开发了平面二维水流数学模型和船舶操纵运动数学模型,对模型的合理性和可靠性进行验证后,通过模拟横流作用下的船舶运动,研究了超标横流对船舶横漂速度和漂角的影响,提出了超标横流安全范围和航道定量加宽值。实例应用表明:在传统航道尺度设计下,当支流口超标横流范围较小时可通过调整舵角实现航行安全;而当超标横流范围较大时则难以保障船舶安全通航,需进行河道加宽设计。提出的超标横流条件下航道加宽确定方法基本合理,对船舶操纵运动和航道设计具有一定参考价值。

长江下游支流入江段水文河势特征与治理对策研究

皖河为长江安徽段最大支流,其入江段受上游来流与长江顶托的双重作用,河势复杂多变。针对皖河下游入江段特殊的水文情势,系统开展皖河与长江干流水位-流量关系研究,分析了近期水旱灾害情景;从河道平面形态、滩槽冲淤变化以及长江交汇口河道纵横向变化等方面,系统分析了皖河下游入江段的演变特征;通过建立二维水动力数学模型,研究了洪灾、旱灾形势下皖河下游入江段水流特性。结果表明:安庆站水位在10.40 m以上时,长江干流水位是影响皖河下游水位的主导因素,而安庆站水位低于10.40 m时,上游来流量成为影响皖河下游水位的主要因素;2008年以来皖河八里湖至入江口段河槽小幅冲刷,大面积滩地淤积,平均淤积厚度为1~2 m,局部厚度可达3~4 m,河段滩地总淤积量约0.58亿m~3;枯水时皖河入江口江水倒灌,洪水受长江顶托和左右岸密集建筑物的约束,入江口存在低流速回流区域,导致回流区泥沙易落淤以及洪水宣泄不畅。在此基础上,研判该河段防洪抗旱、航运发展、水资源利用等方面的治理需求,提出了新建控制性水利枢纽、提高堤防等级以及开展航道疏浚工程等治理对策,以提高皖河流域航运与水旱灾害防御能力。

引江济淮干支交汇处通航水流条件分析

以引江济淮江淮沟通段、菜子湖段支流入汇为实例,针对其典型交汇段存在的复杂通航水流条件,运用数值模拟的方法,对比所选汇流口工况下交汇水域的横流分布,同时分析河道横比降,以此评价河段通航水流条件的安全性。根据研究结果:最大横流区位于汇流口靠近下游位置,横流值成放射状向对岸递减,且在此处横比降最大,此区域应视为通航最危险区域。随着汇流比、支流入汇角的增大,交汇区域横流值、横比降峰值递增。当支流入汇角为30°、汇流比为0.7和支流入汇角90°、汇流比为0.2时,河道通航环境相对安全,其余工况均存在不同程度的通航风险。研究结果可为江淮沟通段、菜子湖段其他交汇水域的通航安全评价提供一定的技术支撑。

东江河口典型河段溶解氧时空动态及低氧成因解析

为解析东江南支流低氧现象的成因,并为水环境治理提供科学依据,本研究分别于2019年春季和夏季对该河流的主要断面进行了水质监测。监测结果显示,东江南支流的溶解氧(DO)水平从中游道滘镇的6.93 mg/L降至出海口处的4.08 mg/L。DO与影响因子的相关性分析显示,DO与水温呈显著负相关,与盐度呈正相关,而与氨氮和总磷等营养物质呈显著负相关。这些营养物质的增加与DO的降低在空间上呈显著重叠,特别是在夏季。研究结果表明,东江南支流低氧现象受物理、化学和生物因素的共同影响,其中温度升高和营养物质浓度增加使得中下游水体的氧气消耗加快,河道汇流处的断面缩窄和下游水体的透光性差引起DO补给不足,从而导致下游沙田泗盛断面经常性出现氧亏(低氧)现象。

面子与里子之间:宋代却贡探微

却贡即退还贡品,是中国古代朝贡制度中的特殊现象,降及宋代,其出现频率拔升。宋朝通过却贡以满足在政治上维护“天朝上国”地位;军事上保障边境和国内安全;经济上减轻负担的现实需求。此外,还会出于厚民生、显仁德的道德使命感对奇珍异兽、劳民伤财的物品进行退还或禁止进贡。宋代却贡对当时的政治、经济、军事产生了重要作用,同时规范和完善了古代的朝贡制度,其中暗含的生态观念对当今仍有重要启示。

十大孔兑复合侵蚀区泥沙阻控与近自然生态修复关键科学技术问题

十大孔兑复合侵蚀区水力侵蚀严重、产沙输沙机理复杂、治理难度大、流域水沙风沙入黄量大、生态系统稳定性差。在阐述区域防沙治沙背景、研究现状与目标基础上,指出需要解决的3个重大关键科学问题:十大孔兑复合侵蚀及洪沙产输的驱动机制,维持植被生态系统稳定性的广义水资源承载力及其阈值,十大孔兑泥沙阻控技术和近自然生态修复技术研发与集成。归纳科技创新项目拟解决的关键技术问题,并梳理分解为6个方面的研究内容:风水复合水土流失过程辨识及水沙合理处置的生态修复空间区划,基于不同生态修复空间布局和乡土植物优化配置的泥沙有效阻控技术研发,山水林田湖草沙多维梯级协同治理技术研发,基于水资源刚性约束的人工退化植被稳定性维持与提质增效技术研发,多位一体近自然生态修复技术体系与模式构建,罕台川丘陵沟壑区、达拉特旗“三北”工程治理区、黑赖沟恩格贝生态建设区等示范研究。

秦“道”制起源新论

战国时期,秦国在统一进程中,根据被征服地区的顺逆程度,对新征服的非秦族群地区采取置郡县直辖和设立附属臣邦两种模式。秦属臣邦在保留原有“王侯君长”的同时,设置官员进行监督导化,秦“道”制即起源于臣邦中的“道官”系统,并在臣邦秦制化的过程中得到完善,发展为管理非华夏族群地区的与县平级的地方行政机构。从秦简文与封泥材料看,“道”即“導”,“道”制本意就是导化蛮夷,与交通道路无关。臣邦与“道”的主官为“丞”,意为辅佐,隐含“導”义,与县、都官主官称呼有别。

明清鼎革期间明将毛文龙与朝鲜关系研究

明清鼎革之际,明与后金之间的军事争夺时有发生,双方争夺的结果直接决定了谁将成为未来东亚宗藩体系的领导者。在看似明确的敌我对抗和表面的新旧交替背后,还潜藏着宗藩体系内部成员的观望与自保、多方勾连甚至待价而沽。毛文龙作为明将代表明朝在朝鲜履行保护朝鲜国家安全的义务,但却卷入了明、后金与朝鲜三方博弈的漩涡之中。朝鲜作为明朝宗藩体系最亲近的一员,一方面与毛文龙互相袒护与猜忌,一方面又与后金保持半臣属状态。无疑,明将毛文龙与朝鲜关系为我们提供了一个观察明清鼎革前夜东亚宗藩体系内部关系实态的理想视角。

唐朝限制贡人法律研究

蕃国不时向中原朝贡人口,被朝贡者主要有歌舞艺人、与宗教相关的人、有特殊技艺的人及奴隶等。从立国的唐高祖,到唐朝后期的唐懿宗,许多皇帝发布过限制蕃国朝贡人口的诏令。唐朝限制贡人法律以诏敕为主要形式,代表和维护了最高统治者与百姓利益,但缺乏相应的制裁措施。在唐朝的不同时期,唐朝限制贡人法律的实施并不尽如人意。唐太宗、唐玄宗、唐代宗、唐德宗及唐穆宗等皇帝都接受过蕃国贡人。唐朝限制贡人法律实施不理想的原因,主要是皇帝仅仅表明一种态度(节俭或悲悯),缺乏制裁措施以及限制贡人法律难以告知所有蕃国等。