特大型屋面与地面雨水收集系统的应用分析

以某特大型屋面及地面雨水收集系统项目为例,对特大型屋面与地面雨水收集系统进行概述,介绍了其雨水弃流过滤方式、雨水蓄水池的形式以及雨水处理工艺,探究了该系统的应用难点,并具体分析了有关雨水收集系统的应用,以保证特大型雨水收集系统的稳定运行.     

A framework for statistical clustering with constant time approximation algorithms for K-median and K-means clustering

We consider a framework of sample-based clustering. In this setting, the input to a clustering algorithm is a sample generated i.i.d by some unknown arbitrary distribution. Based on such a sample, the algorithm has to output a clustering of the full domain set, that is evaluated with respect to the underlying distribution. We provide general conditions on clustering problems that imply the existence of sampling based clustering algorithms that approximate the optimal clustering. We show that the K-median clustering, as well as K-means and the Vector Quantization problems, satisfy these conditions. Our results apply to the combinatorial optimization setting where, assuming that sampling uniformly over an input set can be done in constant time, we get a sampling-based algorithm for the K-median and K-means clustering problems that finds an almost optimal set of centers in time depending only on the confidence and accuracy parameters of the approximation, but independent of the input size. Furthermore, in the Euclidean input case, the dependence of the running time of our algorithm on the Euclidean dimension is only linear. Our main technical tool is a uniform convergence result for center based clustering that can be viewed as showing that the effective VC-dimension of k-center clustering equals k. Editor: Olivier Bousquet and Andre Elisseeff A preliminary version of this work appeared in the proceedings of COLT’04 (Ben-David, 2004). This work is supported in part by the Multidisciplinary University Research Initiative (MURI) under the Office of Naval Research Contract N00014-00-1-0564.     

Changes in antinutrients,phenolics, antioxidant activities and in vitro α-glucosidase inhibitory activity in pumpkin leaves (Cucurbita moschata) during different domestic cooking methods

Food Science and Biotechnology - Pumpkin leaves (Cucurbita moschata) were subjected to different household cooking methods (boiling, microwaving, steaming, and stir-frying) to evaluate their effect...     

Loss of Fer Jeopardizes Metabolic Plasticity and Mitochondrial Homeostasis in Lung and Breast Carcinoma Cells

Metabolic plasticity is a hallmark of the ability of metastatic cancer cells to survive under stressful conditions. The intracellular Fer kinase is a selective constituent of the reprogramed mitochondria and metabolic system of cancer cells. In the current work, we deciphered the modulatory roles of Fer in the reprogrammed metabolic systems of metastatic, lung (H358), non-small cell lung cancer (NSCLC), and breast (MDA-MB-231), triple-negative breast cancer (TNBC), carcinoma cells. We show that H358 cells devoid of Fer (H358ΔFer), strictly depend on glucose for their proliferation and growth, and fail to compensate for glucose withdrawal by oxidizing and metabolizing glutamine. Furthermore, glucose deficiency caused increased reactive oxygen species (ROS) production and induction of a DNA damage response (DDR), accompanied by the onset of apoptosis and attenuated cell-cycle progression. Analysis of mitochondrial function revealed impaired respiratory and electron transport chain (ETC) complex 1 (comp. I) activity in the Fer-deficient H358ΔFer cells. This was manifested by decreased levels of NAD⁺ and ATP and relatively low abundance of tricarboxylic acid (TCA) cycle metabolites. Impaired electron transport chain comp. I activity and dependence on glucose were also confirmed in Fer-deficient, MDA-MB-231ΔFer cells. Although both H358ΔFer and MDA-MB-231ΔFer cells showed a decreased aspartate level, this seemed to be compensated by the predominance of pyrimidines synthesis over the urea cycle progression. Notably, absence of Fer significantly impeded the growth of H358ΔFer and MDA-MB-231ΔFer xenografts in mice provided with a carb-deficient, ketogenic diet. Thus, Fer plays a key role in the sustention of metabolic plasticity of malignant cells. In compliance with this notion, targeting Fer attenuates the progression of H358 and MDA-MB-231 tumors, an effect that is potentiated by a glucose-restrictive diet.     

Correction to: Evaluation of publication delays in the orthopedic surgery manuscript review process from 2010 to 2015

Scientometrics - In the original publication of the article, the author’s name “Shai Shemesh” was missed. The complete author group is given in this Correction.     

Adaptive Anisotropic Total Variation: Analysis and Experimental Findings of Nonlinear Spectral Properties

Journal of Mathematical Imaging and Vision - Our aim is to explain and characterize the behavior of adaptive total variation (TV) regularization. TV has been widely used as an edge-preserving...     

CNG储气井套管接头最佳上扣扭矩研究

上扣扭矩值的大小是CNG储气井发生失效的主要影响因素之一。以覫177.8 mm×10.36 mm套管为研究对象,利用ANSYS软件分别在套管和管箍螺纹之间施加不同的上扣过盈(啮合)圈数并对其进行有限元分析。通过模拟计算来研究套管螺纹上接触应力的分布以及上扣扭矩值的变化情况,确定出合理的过盈圈数以使上扣扭矩达到最佳值,进而有效地防止失效的产生。     

A magnetorheological polishing-based approach for studying precision microground surfaces of tungsten carbides

Surface features of tungsten carbide composites processed by bound abrasive deterministic microgrinding and magnetorheological finishing (MRF) were studied for five WC–Ni composites, including one binderless material. All the materials studied were nonmagnetic with different microstructures and mechanical properties. White-light interferometry, scanning electron microscopy, and atomic force microscopy were used to characterize the surfaces after various grinding steps, surface etching, and MRF spot-taking. It was found that the peak-to-valley (p–v) microroughness of the surface after microgrinding with rough or medium abrasive size tools gives a measure of the deformed layer depth. MRF spots revealed the true depth of the grinding-induced deformed surface layer.     

李子箐风电场风机基础三维有限元分析

采用大型通用有限元分析软件ANSYS,对李子箐风电场风机基础进行三维有限元计算,探讨了在正常运行工况下,风机基础及地基的应力和变形规律,了解基础和地基在设计条件下的工作形态,为施工组织设计提供参考依据。