Compression molding and melt‐spinning of the blends of poly(lactic acid) and poly(butylene succinate‐co‐adipate)

Poly(lactic acid) (PLA) is a biobased polymer made from biomass having high mechanical properties for engineering materials applications. However, PLA has certain limited properties such as its brittleness and low heat distortion temperature. Thus, the aim of this study is to improve toughness of PLA by blending with poly(butylene succinate‐co‐adipate) (PBSA), the biodegradable polymer having high toughness. Polymer blends of PLA and PBSA were prepared using a twin screw extruder. The melt rheology and the thermal property of the blends were examined. Further the blends were fabricated into compression molded parts and melt‐spun fiber and were subjected to tensile and impact tests. When the PBSA content was low, PBSA phase was finely dispersed in the PLA matrix. On the other hand, when the PBSA content was high, this minor phase dispersed as a large droplet. Mechanical properties of the compression molded parts were affected by the dispersion state of PBSA minor component in PLA matrix. Impact strength of the compression molded parts was also improved by the addition of soft PBSA. The improvement was pronounced when the PBSA phase was finely dispersed in PLA matrix. However, the mechanical property of the blend fibers was affected by the postdrawing condition as well as the PBSA content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41856.     

Data Squashing by Empirical Likelihood

Data squashing was introduced by W. DuMouchel, C. Volinsky, T. Johnson, C. Cortes, and D. Pregibon, in Proceedings of the 5th International Conference on KDD (1999). The idea is to scale data sets down to smaller representative samples instead of scaling up algorithms to very large data sets. They report success in learning model coefficients on squashed data. This paper presents a form of data squashing based on empirical likelihood. This method reweights a random sample of data to match certain expected values to the population. The computation required is a relatively easy convex optimization. There is also a theoretical basis to predict when it will and won't produce large gains. In a credit scoring example, empirical likelihood weighting also accelerates the rate at which coefficients are learned. We also investigate the extent to which these benefits translate into improved accuracy, and consider reweighting in conjunction with boosted decision trees.     

Detection techniques for MIMO spatial multiplexing systems

We discuss and compare the most important detection techniques for MIMO spatial multiplexing wireless systems, focusing on their performance and computational complexity. Our analysis shows that the limited performance of conventional suboptimal detection techniques is primarily caused by their inability to cope with poorly conditioned channels. The recently proposed sphere projection algorithm is better suited to these channels and can achieve near-optimal performance.     

审美抑或社会性问题——刘家琨艺术学校系列剖析

本文以大量翔实的一手资料为基础，剖析了刘家琨建筑师设计的艺术学校系列在其个人实践生涯中的呈现和意义，同时也阐释了这些作品所体现的对社会性、资源的当代性问题的态度，以及在建筑的艺术性方面对叙事语言、建构语言与建筑的功能性“表皮”等问题的探索。     

您需要多少示波器带宽?

示波器带宽是决定示波器价格的主要因素.本文以大多数现代示波器更接近砖墙滤波器为基础,论述了在你测量所需要的示波器带宽,将有助于你购买多少带宽的示波器.     

室内环境设计与装饰装修

通过对室内环境设计与装饰装修自身特点以及前存在问题的剖析。提出了室内环境设计与装饰装修的三条基本原则：以“人”为中心的原则；以“文化”为基调的原则以及与各相关系统相统一的原则。     

房产交易与信息发布系统的开发及实现

综合考虑了一般房产管理的运行模式和现有的网络地理信息系统实现方法,在探索一个性能价格比高的房产交易与信息发布系统的实现方法的基础上,提出了一种基于Internet或Intranet上的房产交易管理信息系统模型模式;采用网络的主流技术ASP,同时结合ESRI公司的ArcIMS用SQLSERVER2000数据库实现房产交易管理和房产信息发布。     

A simple computational model for analyzing the properties of stop-loss,take-profit,and price breakout trading strategies

Stop-loss, take profit and price breakout strategies, though in some ways theoretically unattractive, are nonetheless popular with traders. We describe and illustrate a simple, fast, flexible and practical discrete time computational model for performing probabilistic analyses of the risks, rewards and tradeoffs associated such strategies.