Navigating the tensions in collaborative watershed governance: Water governance and Indigenous communities in British Columbia,Canada

First Nations in British Columbia (BC), Canada, have historically been—and largely continue to be—excluded from colonial governments’ decision-making and management frameworks for fresh water. However, in light of recent legal and legislative changes, and also changes in water governance and policy, there is growing emphasis in scholarship and among legal, policy and advocacy communities on shifting water governance away from a centralized single authority towards an approach that is watershed-based, collaborative, and involves First Nations as central to decision-making processes. Drawing on community-based research, interviews with First Nations natural resource staff and community members, and document review, the paper analyzes the tensions in collaborative water governance, by identifying First Nations’ concerns within the current water governance system and exploring how a move towards collaborative watershed governance may serve to either address, or further entrench, these concerns. This paper concludes with recommendations for collaborative water governance frameworks which are specifically focused on British Columbia, but which have relevance to broader debates over Indigenous water governance.     

Acoustic radiation from shear deformable ring-stiffened laminated composite cylindrical shell submerged in flowing fluid

Acoustic radiation from a point driven, infinite, periodically ring-stiffened, laminated composite cylindrical shell submerged in flowing fluid is investigated theoretically. Both the effects of in-plane and out-of-plane vibrations of the ring-stiffeners and the effects of fluid convection on far field acoustic radiation behaviors are concerned. The equations of motion of the laminated composite cylindrical shell is presented on the basis of the first order shear deformation theory. Fourier transform and Poisson summation formula are used to transform the equations into a set of infinite algebraic equations expressed in the wavenumber domain. After truncation, the response of the laminated composite cylindrical shell is solved, and the stationary phase approximate is employed to find the expression for the far field sound pressure. Convergence analysis of the numerical solutions is conducted. The theoretical model and numerical method proposed in this paper are validated by comparison with those presented in available literature. Finally, numerical results are presented to demonstrate the effects of various parameters such as the size and spacing of the ring-stiffener, the thickness and the radius of the cylindrical shell, the lamination angle and the lamination scheme of the composite materials as well as the Mach number on the far field sound pressure.     

异步时序设计亚稳态的消除方法

提出一种基于异步比较法产生空满标志位，并利用锁存器实现标志位与时钟同步的FIFO，同时还给出了相应的Verilog HDL代码。该方法能提高时钟频率,节约版图面积。     

一个FUZZY聚类分析的快速算法

Fuzzy聚类分析,是近年来在气象预报等很多科学领域中广泛应用的一种客观分析技术。本文根图的可迁闭包性质,探讨从模糊相似矩阵R中节点的可达性问题着手,生成相应的深度优先生成树(DFT)来完成聚类,从而得到一个时间复杂性为O(n~2)的快速Fuzzy聚类算法。     

Tree-ring dates on two pre-Little Ice Age advances in Glacier Bay National Park and Preserve, Alaska, USA

Two interstadial tree ring-width chronologies from Geikie Inlet, Glacier Bay Southeast, Alaska were built from 40 logs. One of these chronologies has been calendar dated to AD 224–999 (775 yr) crossdating with a living ring-width chronology from Prince William Sound, Alaska. Trees in this chronology were likely killed through inundation by sediments and meltwater from the advancing Geikie Glacier and its tributaries ca. AD 850. The earlier tree-ring chronology spans 545 yr and is a floating ring-width series tied to radiocarbon ages of about 3000 cal yr BP. This tree-ring work indicates two intervals of glacial expansion by the Geikie Glacier system toward the main trunk glacier in Glacier Bay between 3400 and 3000 cal yr BP and again about AD 850. The timing of both expansions is consistent with patterns of ice advance at tidewater glaciers in other parts of Alaska and British Columbia about the same time, and with a relative sea-level history from just outside Glacier Bay in Icy Strait. This emerging tree-ring dated history builds on previous radiocarbon-based glacial histories and is the first study to use tree-ring dating to assign calendar dates to glacial activity for Glacier Bay.     

A 2000-yr-long multi-proxy lacustrine record from eastern Baffin Island, Arctic Canada reveals first millennium AD cold period

We generate a multi-proxy sub-centennial-scale reconstruction of environmental change during the past two millennia from Itilliq Lake, Baffin Island, Arctic Canada. Our reconstruction arises from a finely subsectioned ²¹⁰Pb- and ¹⁴C-dated surface sediment core and includes measures of organic matter (e.g., chlorophyll a; carbon–nitrogen ratio) and insect (Diptera: Chironomidae) assemblages. Within the past millennium, the least productive, and by inference coldest, conditions occurred ca. AD 1700–1850, late in the Little Ice Age. The 2000-yr sediment record also reveals an episode of reduced organic matter deposition during the 6th–7th century AD; combined with the few other records comparable in resolution that span this time interval from Baffin Island, we suggest that this cold episode was experienced regionally. A comparable cold climatic episode occurred in Alaska and western Canada at this time, suggesting that the first millennium AD cold climate anomaly may have occurred throughout the Arctic. Dramatic increases in aquatic biological productivity at multiple trophic levels are indicated by increased chlorophyll a concentrations since AD 1800 and chironomid concentrations since AD 1900, both of which have risen to levels unprecedented over the past 2000 yr.     

2012 年天津宝坻2 次有感地震的力学机制研究

利用地震仪器烈度分布、地震记录初动极性分布、近场地震序列Sg 震相剪切波分裂特征、震中附近应变仪器记录及深井气氦记录等,综合分析了宝坻地区2012 年MS 4. 0、MS 3. 5两次有感地震。研究发现,这2 次地震震级不大,但孕震过程可能伴有地下介质应力状态的变化,表现出震前半年北东东向加速压缩、北北西向拉张至MS3. 5 地震后该状态转缓的动态过程。2 次地震间隔期间地下积累应力疑似没有得到充分释放,地下微裂隙局部调整使得该地深井观测的稀有气体出现高值,MS 3. 5 地震后微裂隙重新闭合,稀有气体恢复背景值,同时地震剪切波快波方位角恢复到北东东向的背景方向。震中区附近的形变、测震、流体等观测异常有一定的时空对应性。     

CST-based first order second moment method for probabilistic slope stability analysis

Correlated random variables are commonly involved in probabilistic slope stability analysis, such as reliability analysis of slopes with spatially variable soil properties. This paper proposes a simple Correlated Sampling Technique (CST) for generating samples of correlated random variables. The CST firstly produces correlated standard-normally distributed samples through linear combinations of independent standard-normally distributed samples. Correlated arbitrarily distributed samples can then be obtained by the Nataf transformation. The CST was combined with FOSM (named CST-based FOSM) for probabilistic slope stability analysis. The slope reliabilities of a single-layered cohesive soil slope and a high earth and rockfill dam were analyzed to illustrate the CST-based FOSM. These illustrative examples indicated that the CST-based FOSM can accurately estimate the slope reliability indices with considerably fewer simulations (especially in the case of low failure probability) compared with direct MCS, and the slope reliability was sensitive to the correlation of the strength parameters.