Enhancements to GPS operations and clock evaluations using a "total" Hadamard deviation

We describe a method based on the total deviation approach whereby we improve the confidence of the estimation of the Hadamard deviation that is used primarily in global positioning system (GPS) operations. The Hadamard-total deviation described in this paper provides a significant improvement in confidence indicated by an increase of 1.3 to 3.4 times the one degree of freedom of the plain Hadamard deviation at the longest averaging time. The new Hadamard-total deviation is slightly negatively biased with respect to the usual Hadamard deviation, and tau values are restricted to less than or equal to T/3, to be consistent with the usual Hadamard's definition. We give a method of automatically removing bias by a power-law detection scheme. We review the relationship between Kalman filter parameters and the Hadamard and Allan variances, illustrate the operational problems associated with estimating these parameters, and discuss how the Hadamard-total variance can improve management of present and future GPS satellite clocks.     

Drug and alcohol use among drivers admitted to a Level-1 trauma center

The purpose of this research was to determine the incidence and prevalence of drug use, alcohol use, and the combination of drug and alcohol use among motor vehicle crash (MVC) victims admitted to a Level-1 trauma center. In a 90-day study, nearly two-thirds of trauma center admissions were victims of motor vehicle crashes. Blood and urine was collected from 168 MVC victims of whom 108 were identified as the driver in the crash. Toxicology results indicated that 65.7% of drivers tested positive for either commonly abused drugs or alcohol. More than half of the drivers tested positive for drugs (50.9%) other than alcohol, with one in four drivers testing positive for marijuana use. About one-third of those using drugs had also been drinking, but alcohol was detected in only 30.6% of all injured drivers. Within the total MVC patient pool, passenger drug/alcohol use was equivalent to the driver population; however, injured pedestrians had higher rates of alcohol only than other MVC victims. There were no significant differences in drug and alcohol use between MVCs and trauma admissions of other causes. Of the patients with positive toxicology results, less than half (42%) were referred for evaluation for substance abuse disorders.     

How to Apply Advanced Statistical Analysis to Computational Economics: Methods and Insights

The theme of this special volume concerns advanced statistical analysis. By mining meaningful and important information, advanced statistical analysis can bring new insights to many areas, such as the development of hospitals, the environment, biology, markets, industries, and general economic systems. The contribution of this special volume is to adopt an advanced parametric and nonparametric statistical approach for the exploration of environmental and health care issues in the context of computational economics. The authors have proposed varied methods of advanced statistical analysis combined with practical applications. In terms of theory, the authors suggest designs for advanced theoretical methods. With regard to the application of professional calculation methods to everyday life, the authors have offered useful guidance for future research. The authors have also conducted empirical research by using data from Chinese regions and analyzing specific conditions. In addition, they have conducted empirical analyses of particular issues such as those related to the environment. Although this special volume has provided some methods of advanced scientific analysis for existing problems, other techniques must be applied to everyday life in order to solve the severe difficulties that human beings face.     

Welding of Very Dissimilar Materials (Fe-Al)

Designers of transportation vehicles (air, land, or sea) continually seek ways to reduce vehicle weight in response to increasing fuel economy mandates, mission requirements, or other competitive pressures. One way to do this is by the selection of material types and their properties based on functional and structural requirements. While these material changes can help meet performance mandates, their implementation in a production environment relies on retaining economic competitiveness. This article traces the history of the various joining processes relevant to the current challenge in joining the very dissimilar families of steel (Fe) and aluminum (Al) alloys.     

Continuous production of flexible carbon nanotube-based transparent conductive films

This work shows a simple, single-stage, scalable method for the continuous production of high-quality carbon nanotube-polymer transparent conductive films from carbon feedstock. Besides the ease of scalability, a particular advantage of this process is that the concentration of nanotubes in the films, and thus transparency and conductivity, can be adjusted by changing simple process parameters. Therefore, films can be readily prepared for any application desired, ranging from solar cells to flat panel displays. Our best results show a surface resistivity of the order of 300 Ω square^-1 for a film with 80% transparency, which is promising at this early stage of process development.     

RF：究竟能否成为插入式Ⅰ?

对于下一代智能手机、移动视频播放器以及Web漫游附件的整合,其含意不仅是要将多用途基带与应用处理器、加速器和内存一起放到同一片SoC(系统单芯片)上,而且还要将许多小信号RF电路整合到SoC上.其中就存在一项重人难题.     

流量管理SoC设计者越来越大的梦魇

SoC（系统级芯片）在先于它出现的板级计算机上开始了自己的生命;作为一个中央处理器,其CPU总线连接到本地内存与外设控制器。从此以后,这种以CPU为中心、面向总线的架构一直是很多SoC的优先规划。