Online Ideology: A Comparison of Website Communication and Media Use

This study examined and compared the websites of ideological groups from a communications and media use perspective. Thirty‐six websites with message boards categorized as either violent ideological, nonviolent ideological, or nonviolent nonideological were content coded for several distinguishing characteristics. The results indicated that group type was predicted by the type of information presented, the difficulty of becoming a member, and the amount of freedom members had on discussion boards. These findings suggest that characteristics of violent ideological group websites can be used to distinguish them from websites of both nonviolent ideological and nonideological groups. This study also provides a demonstration of a research methodology that can be used to naturally observe ideological groups via an online setting.     

A new torque minimization method for heavy-duty redundant manipulators used in nuclear decommissioning tasks

Intelligent Service Robotics - This paper presents an approach to optimize the control torque of heavy-duty redundant manipulators used for dismantling nuclear power plants. Such manipulators must...     

War Driving and WLAN Security Issues—Attacks,Security Design and Remedies

ABSTRACT

Mobile computing is evolving at a rapid pace with 802.11 networks; the fuzzy boundaries make it easy for intruders to intercept the radio signals. War driving was performed along highways; the resulting packet analysis is explained to show how easy some security attacks can be. An elaboration is done on a host of wireless security attacks that leads to the discussion of secure wireless network design, along with some network security simulation. The paper concludes with a list of security recommendations.     

Identification for the robust control of robot manipulators

In this paper an identification scheme, which yields bounds on unmodelled dynamics along with an estimate for the parameters of a nominal dynamic model, has been presented. These estimates are useful for designing a robust controller for trajectory control of robot manipulators, if they satisfy certain conditions. These conditions have been stated mathematically. Guidelines are provided for selecting a data set for identification such that the obtained estimates satisfy the above conditions. Simulation results are presented for a two‐link serial manipulator, when frictional torques are treated as unmodelled. Copyright © 2001 John Wiley & Sons, Ltd.     

Reflection of ultrasonic waves from imperfect interfaces: A combined boundary element method and independent scattering model approach

A numerical technique for obtaining interface reflection coefficients for imperfect bonds between similar materials for a wide range of distributed defects is developed. A numerical boundary element method is utilized to find the far-field scattering amplitudes of a single defect for a normally incident plane wave. Then, the normal incidence reflection coefficient for a planar distribution of such defects is obtained from the independent scattering model. As a validation, the reflection coefficients are compared to the quasi-static model results where the latter are available. This establishes the basis for one application of the new model, the determination of spring constants which are not available. Other applications of the model, including studies of the response at frequencies beyond the quasi-static limit, the ratio of longitudinal to transverse wave reflectivities, and the effects of selected multiple scattering are discussed.     

A 70-MHz Continuous-Time CMOS Band-Pass ΣΔ Modulator for GSM Receivers

A 70-MHz continuous-time CMOS band-pass modulator for GSM receivers is presented. Impulse-invariant-transformation is used to transform a discrete-time loop-filter transfer function into continuous-time. The continuous-time loop-filter is implemented using a transconductor-capacitor (G _m -C) filter. A latched-type comparator and a true-single-phase-clock (TSPC) D flip-flop are used as the quantizer of the modulator. Implemented in a MOSIS HP 0.5-m CMOS technology, the chip area is 857 m × 420 m, and the total power consumption is 39 mW. At a supply voltage of 2.5 V, the maximum SNDR is measured to be 42 dB, which corresponds to a resolution of 7 bits.     

Reasons for quitting smoking among low-income African American smokers.

The psychometric characteristics of the Reasons For Quitting scale (RFQ) were assessed among a sample of African American smokers with low income (N?=?487). The intrinsic and extrinsic scales and their respective subscales were replicated. As hypothesized, higher levels of motivation were associated significantly, in patterns that supported the measure's construct validity, with advanced stage of readiness to quit smoking, greater perceived vulnerability to health effects of smoking, and greater social support for cessation. On the basis of the present study, the RFQ might best predict short-term cessation among older and female smokers. Refinement of the RFQ is needed to assess intrinsic motivators other than health concerns and to identify salient motivators for young and male smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

一种基于时间序列模型的风速预测方法

根据风速数据特点,提出一种基于时间序列的风速预测模型,对模型中的相关参数进行确定。实验结果表明,对风速进行提前1小时预测时,预测风速与实际风速较吻合,误差仅为10%,从而为大气污染物浓度确定提供有效依据。     

Modern Microalloyed Steels

The addition of microalloying elements (MAE) to low C-Mn-Si HSLA steels has led to many benefits to the producers,fabricators and end-users.Microstructural improvements such as microstructural refinement,higher dislocation and sub-grain boundary densities and finer M-A-C distributions have led to higher strength,improved toughness and better formability.These improvements can often be traced to the MA addition.In steels for load-bearing applications,the combination of MAE with hardenability additions (Cr,Mo,B,etc.) and lower transformation temperatures has led to much higher strength levels than what were available a few years ago.The resulting nonpolygonal,bainitic and martensitic ferrite microstructures have not only higher strengths but also adequate levels of improved ductility and toughness.Hot strip,plate and pipe applications have benefitted from these developments.Similar improvements have been found in the microalloyed forging steels,where the change from pearlite-ferrite to bainitic ferrite microstructures has led to higher strengths and improved high-cycle fatigue resistance,with little penalty in ductility and toughness.In the cold rolled gauges,both the so-called Advanced High Strength Steels (DP,TRIP and Complex Phase Steels) and the martensitic direct-quenched and press-quenched steels,along with the Interstitial-Free steels,have benefited from MAE additions,especially in the very popular zinc-coated sheet form.This paper will briefly review each of these topic areas,and the underlying physical metallurgy will be discussed.