Early intervention for spelling problems: Teaching functional spelling units of varying size with a multiple-connections framework.

Poor spellers in 2nd grade (n?=?128) participated in 24 20-min sessions that included (a) direct instruction in the alphabet principle (most frequent phoneme-spelling connections); (b) modeling of different approaches, singly and in combination, for developing connections between spoken and written words for 48 words ordered by sound-spelling predictability; and (c) practice in composing. Results of this multilayered intervention showed that (a) more than 1 way of developing sound-spelling connections is effective in teaching spelling but that after training in the alphabet principle, combining whole word and onset-rime training is most effective in achieving transfer of the alphabet principle across word contexts; (b) functional spelling units of not only a single letter but also 2 or more letters are important in beginning spelling; and (c) training in spelling transfers to composition and word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluating Ozone as a Remedial Treatment for Removing RDX from Unsaturated Soils

Years of wastewater discharge at the Department of Energy’s Pantex Plant have contaminated the vadose zone and underlying perched aquifer with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Because the vadose zone is acting as a continual source of groundwater contamination, removing RDX from the unsaturated zone is paramount to prevent further contamination. We determined the efficacy of ozone to degrade and mineralize RDX. Solution experiments showed that ozone (27?mg?L?1; 150?mL?min?1) was effective in mineralizing 80% of the RDX (30?mg?RDX?L?1) provided that some Pantex soil was present to buffer the solution pH. Soil columns treated with ozone produced 50% RDX mineralization within 1 day and >80% within 7 day. Experiments designed to evaluate aerobic biodegradation following partial ozonation of a RDX solution showed that ozone-generated RDX products were much more biodegradable than untreated controls in aerobic microcosms (35 versus <0.3% cumulative mineralization). These results support the use of ozone as a remedial treatment for the contaminated vadose zone at the Pantex facility.     

Visual insights into high-resolution earthquake Simulations.

This study focuses on the visualization of a series of large earthquake simulations collectively called TeraShake. The simulation series aims to assess the impact of San Andreas Fault earthquake scenarios in Southern California. We discuss the role of visualization in gaining scientific insight and aiding unexpected discoveries.     

Trouble at the Telco: When GSM Goes Bad

GSM is a series of standards defining various aspects of mobile voice and data communications. These standards provide a framework that looks set to underlie modern mobile business communications well into the 21st century.     

A Unified Approach to Submicron DC MOS Transistor Modeling for Low-Voltage ICs

A unified single-equation approach for the MOS transistordrain current modeling for energy-efficient submicron MOS circuitsis presented. Instead of three sets of separate equations forthe triode, saturation, and weak inversion regions, only a continuousexpression which is valid to describe the behavior of drain currentand the derivatives in all operation regions can be realizedby using a combination of hyperbola, sigmoid, and interpolationmethods. The model expression can predict accurate results forthe current, output conductance, and transconductance with continuousand smooth characteristics. The simulation results agree wellwith experimental data.     

Fuel choice and aggregate energy demand in the residential and commercial sectors

The energy demand response of the residential and commercial sectors to fuel price changes is of increasing importance to public policy makers. In this paper, the demands for energy in both sectors are examined separately using a refined data base. For each sector, a multinomial logit formulation is utilized, along with an aggregate demand equation to determine analytically short- and long-run fuel price elasticities of demand for the major fuels consumed. It is found that increases in energy prices have a greater effect on energy demand in the commercial sector. Furthermore, in both sectors, raising electricity prices has a greater effect for conserving energy (both end-use and primary) than do equal price rises for natural gas or heating oils.     

在逆境中奋进的蓝牙技术

行业分析人士曾预测,蓝牙半导体市场会在2000年下半年开始攀升,而在2001年将持续攀升.尽管这些预测未达到期待的水平,但普遍地持乐观的态度,蓝牙技术有吸引力的市场仍在向我们召唤.对这一变幻无常的市场,很多半导体供应商趁修改和更新标准之际,纷纷改变了蓝牙产品研发计划.     

Microwave cavity perturbation technique: Part I: Principles

This report reviews the analysis used to extract the complex conductivity of a compound from a microwave cavity perturbation measurement. We intend to present a generalized treatment valid for any spheroidally shaped sample of arbitrary conductivity which is placed at either the electric or magnetic field antinode of the cavity. To begin with, we establish the relationship between the measured parameters and the conductivity for a spherical sample. Next, we extend these results to the case of spheroids; and for the first time, we cover all different configurations that one can possibly use to study an arbitrary conducting sample inside a cavity: in particular, all possible orientations of the sample with respect to the applied field are solved.     

LDMOS射频晶体管满足2.5G和3G蜂窝基站的新挑战

运行在869MHz-2.17GHz频段内的蜂窝无线基站是射频功率晶体替如今最大的市场。其中，基中硅的LDMOS器件被广泛使用于500MHz=2.5GHz之间的射频功率放大器应用当中。作为增强模式的N沟道MOSFET，LDMOS器件(LD代表侧面扩散，描述了器件的沟道结构)专门被设计成为具有高的工作电压(长沟道）和低寄生电容，从而能在高频下工作。在早