OBSERVATION AND REPRESENTATION: ON RECOGNITION AND EXPRESSION OF NATURAL SITES IN LANDSCAPE ARCHITECTURE

In the education of Landscape Architecture, the way we view and depict a natural site is defined by the way we observe and express it. This paper starts with a comparison between the perspective and approach of traditional painting types (the realistic sketch, design sketch, and landscape painting) and those in Landscape Architecture. All of them involve observation (viewing) and expression (drawing) of natural beings and phenomena, where traditional paintings are in the pursuit of honest depiction of the forms or shapes. While in Landscape Architecture it emphasizes understanding and representing the evolutions and the complicated intrinsic relations of the authentic sites — in other words, to represent the nature of reality. To be on-site, the use of body movement, and the evolutions and correlations of natural beings are the three most important principles to the observation and representation in Landscape Architecture. Combining with two cases in teaching and practice, this paper elaborates how to develop abstract forms and design concepts from the observation of authentic sites and how the trans-scaled reflection on the correlations about the sites can inspire a site-scaled design, providing references for the education and practice of Landscape Architecture in China.     

JINHUA MEMORIAL PARK IN SUINING

Observation and representation are the fundamental and core processes and methods in landscape design. By transforming a historical industrial site into an urban cultural park for citizens’ recreational needs, the Jinhua Memorial Park in the Suining City demonstrates how landscape designers observe and represent in post-industrial renewal practice. Designers continuously deepen their understanding of the site through a process from site observation and perception, research and exploration to systematic analyses. During this process, designers were inspired by the industrial production process and textile products, and then applied such concepts in spatial arrangement and prototype for physical renovation. As the skeleton of spatial arrangement, the main road of the campus connects various functional spaces and landscape nodes of the park. Five design strategies, including in-situ preservation, transposition retention, material reuse, appearance protection, and spiritual revitalization, are applied to protect and reorganize the industrial heritages to recall the past prosperous scenes. Landscape design approaches, intuitive or implicit, are adopted to tie up the past, present, and future of the site while making a park that meets the needs of all kinds of users.     

Neighbor embedding XOM for dimension reduction and visualization

We present an extension of the Exploratory Observation Machine (XOM) for structure-preserving dimensionality reduction. Based on minimizing the Kullback-Leibler divergence of neighborhood functions in data and image spaces, this Neighbor Embedding XOM (NE-XOM) creates a link between fast sequential online learning known from topology-preserving mappings and principled direct divergence optimization approaches. We quantitatively evaluate our method on real-world data using multiple embedding quality measures. In this comparison, NE-XOM performs as a competitive trade-off between high embedding quality and low computational expense, which motivates its further use in real-world settings throughout science and engineering.     

小角法在大坝视准线观测中的应用

从观测思路、测点偏离值与位移量计算公式推导、精度分析等几方面阐述了小角法在长度不同的视准线观测中的灵活运用。     

光伏发电系统最大功率点跟踪控制及拓扑结构研究的新进展

本文针对光伏器件的特点提出两种新的最大功率点跟踪控制方法：短路电流结合扰动观察法及用非对称模糊控制的扰动观察法。前一种方法在短路电流控制方法的基础上引入了优化扰动步长的扰动观察法，它可有效消除光伏器件输出功率在最大功率点的振荡现象。第二种方法把非对称模糊控制引入传统的扰动观察法，它在光伏器件最大功率点两侧的特性采取不同的扰动步长，可有效消除传统方法在最大功率点处的功率振荡。仿真和实验研究证明：上述两种方法可以快速跟踪外部环境变化，并消除系统在最大功率点的振荡现象。同时本文提出一种新型的用于小功率光伏发电的高频逆变电路，它由buck－boost变换器和电流源高频链逆变器构成。由它来实现光伏模块的最大功率点跟踪，得到与电网同步的电压。该电路结构简单、效率高，光伏模块的最大功率点不受负载变化的影响。该方案通过实验验证。     

回归分析系统的可靠性理论

根据回归分析基本理论及测量平差理论，讨论了观测误差与观测值残差的关系，指明了残差协因素矩阵及多余观测分量在可靠性理论研究中的特殊作用。并在单个一维备选假设下，将可靠性理论的研究方法引入回归分析系统。提出了回归计算系统的内部可靠性及外部可靠性的概念，以及衡量它们的量化尺度。为在大坝资料中分析中剔除粗差，合理筛选观测数据，提供了理论依据。析     

Estimation of soil water distribution: Identifiability and observation design

Identifiability and observation design problems for the Burgers equation, a model for the nonhysteretic infiltration in nonswelling soil, are considered. In estimating initial water distribution from a finite set of measurements, the identifiability under approximation is proved. In predicting the water distributions, an algorithm for observation design problems is provided and analyzed with the maximum error bound. Also, numerical simulations are performed.     

Rational systems and observation fields

We give a new setting for rational input-output systems, i.e. systems on real affine varieties with the dynamics defined by rational vector fields and with rational output functions. We characterize conditions under which a C∞ system may be immersed into a rational system. The problem of minimal dimension and uniqueness of immersions is also studied. The observation field of the system is the main tool in our considerations.     

葛洲坝水利枢纽大坝垂直位移观测设计的几个问题

本文介绍了在设计时,为设立完整而合理的垂直位移测控系统,对基准点、工作基点、标志和测控网布设的考虑。     

Pointwise uniformly convergent numerical treatment for the non-stationary Burger–Huxley equation using grid equidistribution

This article presents a numerical method for solving the singularly perturbed Burger–Huxley equation on a rectangular domain. That is, the highest-order derivative term in the equation is multiplied by a very small parameter. This small parameter is known as the perturbation parameter. When the perturbation parameter specifying the problem tends to zero, the solution of the perturbed problem exhibits layer behaviour in the outflow boundary region. Most conventional methods fail to capture this layer behaviour. For this reason, there is much current interest in the development of a robust numerical method that may handle the difficulties occurring due to the presence of the perturbation parameter and the nonlinearity of the problem. To solve both of these difficulties a numerical method is constructed. The first step in this direction is the discretization of the time variable using Euler's implicit method with a constant time step. This produces a nonlinear stationary singularly perturbed semidiscrete problem class. The problem class is then linearized using the quasilinearization process. This is followed by discretization in space, which uses the standard upwind finite difference operator. An extensive amount of analysis is carried out in order to establish the convergence and stability of the proposed method. Numerical experiments are carried out for model problems to illustrate graphically the theoretical results. The results indicate that the scheme faithfully mimics the dynamics of the differential equation.