AN-g-casein浓溶液在毛细管流动中的入口效应

采用气压式毛细管流变仪,测定了丙烯腈－酷素接枝共聚物（ＡＮ－ｇ－ｃａｓｅｉｎ）浓溶液的流变性能。利用Ｄｅｗｉｔｔ模型,解析并分离了末端校正中入口效应ζ和可复弹性形变ＳＲ,给出了ζ和ＳＲ与切变速率及温度的定量关系,在测定范围内具有普适性意义,在实际生产中,利用ζ和ＳＲ的普适性方程,只需一根流动曲线,就可求得真实的流变参数。这种解析分离方法也适用于其他粘弹性高聚物。     

Discrete Element Simulation of Collision-Rich Dynamics of Wet Granular Flows Down an Inclined Channel

This paper proposes a numerical scheme that employs the discrete element method (DEM) to simulate the motion of a wet granular flow down an inclined channel. To account for the liquid influences on the dynamics between paired particles, this paper presents a wet soft-sphere contact model with liquid-modified parameters. The developed scheme takes full advantage of DEM and avoids the expensive simulation of the solid-liquid interactions with conventional Navier-Stokes equation solver. This wet contact model has been implemented in an in-housed parallel discrete objects simulation system - KNIGHT and ANNE/IRIS to compute the dynamic behaviors of both dry and wet granular particles flowing down an inclined channel.     

Image Reconstructions from Limit Views and Angle Coverage Data for a Stationary Multi-Pinhole SPECT System

The goal of this paper is to investigate different reconstruction methods for solving the limited angle problem in reconstructing the projection data from a stationary multi-pinhole system based on a three-head clinical single photon emission computed tomography(SPECT) camera.Three iterative reconstruction approaches were studied including maximum likelihood expectation maximization(MLEM),maximum a posteriori expectation maximization(MAPEM) with a smoothing prior,and an alternating optimization schemes from...     

AN-g-casein浓溶液在毛细管流动中的粘弹行为

采用气压式毛细管流变仪，测定了丙烯腈－酷素接枝共聚物（ＡＮ－ｇ－ｃａｓｅｉｎ）浓溶液的流变性能。求得了适合高剪切速率的弹性模量（Ｇ），发现Ｇ随剪切速率的增加而升高，纠正了早原（由于在高剪切速率下仍采用同一个入口校正所造成）的相反结论；定量地求得了表观弹性活化能（Ｅｅ）；在高剪切速率下，可复弹性形变较之表观粘度对于的变化更敏感，是引起孔口膨化的主要原因，采用本文方法，可估算纺丝过程的膨化比，再由此选     

应用遥测技术探讨台湾花莲地区土砂灾害集水区崩塌地的变迁

以1996年、2002年、2005年及2007年四期SPOT卫星影像为材料,配合相关图籍数字化台湾花莲地区寿丰溪集水区与秀姑峦溪集水区的崩塌地图层,透过植生回复率(VRR)、新增崩塌率(ICR)及崩塌地重心位移的计算,探讨这两个集水区崩塌地变迁情形,并分析其环境因子特性. 研究结果显示:利用多期卫星影像数据可有效进行崩塌地长期监测,并获知其变动情形;另突发暴雨可使崩塌大量发生,显为事件直接影响因子;而VRR、ICR与重心位移的计算,可有效量化植生恢复情形及新增崩塌状况;至于地理环境特征方面,崩塌发生概率随高程增加而增加,也与坡度呈正相关,因此未来在开发上应特别留意.     

Design of Optimal Weight for a Gear Transmission System Using Hybrid Taguchi-Genetic Algorithm

The gear transmission system has been widely applied in mechanical systems, and many high-performance applications of these systems require low weight. With the aid of establishing the optimization model of the gear transmission system that consists of an objective function and some constraints (for example, the bending stress, the contact stress, the torsional strength, etc.), the optimal weight design of the gear transmission system can be transformed into the optimization problem for the objective function under the constraints. Moreover, both the shaft and the gear of the gear transmission system are considered simultaneously in our design. The hybrid Taguchi-genetic algorithm (HTGA) is employed to find the optimal design variables and the optimal weight of the system. An illustrated example for the single spur gear reducer is given to show that the optimal weight design problem can be successfully solved using the proposed design scheme. It also proves the high efficiency and feasibility of the algorithm in the gear design.     

AN-g-casein浓溶液在毛细管流动中的末端校正

采用气压式毛细管流变仪，测定了实验室自制丙烯腈－酷素接枝共聚物（ＡＮ－ｇ－ｃａｓｅｉｎ）浓溶液的流变性能。实验结果发现：ＡＮ－ｇ－ｃａｓｅｉｎ浓溶液属切力变稀型非牛顿流体；在实验范围内，毛细管流动中的末端校正系数ｅ随切变速率的提高而增大，当切变速率较高时，ＡＮ－ｇ－ｃａｓｅｉｎ大分子在浓溶液中形成了束状物，拉伸变表受到了限制，ｅ值上升趋于极限；当切变速率较高，毛细管长径比较小时，真实剪切应力仅占表     

台湾地区生态城市发展评价案例

整理全球生态城市相关研究成果,拟定台湾地区生态城市评价指标体系,其架构分为环境、社会、经济等3个层面。其中,环境层面包括了城市绿化、城市环境、环境治理等3部分;社会层面则包括人口结构、居住适宜性、社会保障、资源条件、文化教育等5部分;经济层面则包括产业结构与生产效益两部分。在案例研究中,选择台湾地区台北市、台中市、台南市、高雄市进行比较,结果可知4个城市中以台北市的各项发展现况较接近生态城市指标的理想值。     

Estimating nutrient budgets in a coastal lagoon

To estimate nutrient budgets,water samples were collected at 16 sites in Tapong lagoon from January 2004 through April 2005 and the parameters of water quality were analyzed immediately after collection.These data were used to build a box model for calculating nutrient budgets of the lagoon.We estimated the net amount of nutrient fluxes into (coming from creeks) and out (from tidal inlet) of the lagoon and calculated the total amount of nutrient that deposits into the sediment in a full tidal cycle.During J...