Geotextile encased columns (GEC) used as pressure-relief system. Instrumented bridge abutment case study on soft soil

Geosynthetic Encased Sand Columns (GEC) have been frequently adopted in geo-engineering practice to improve bearing capacity, reduce settlements and accelerate consolidation in saturated soft cohesive ground (e.g. Alexiew et al, 2005; Alexiew et al., 2012; Raithel et al, 2005). The present paper extends these early views by introducing the use of columns to reduce the magnitude of horizontal earth pressures acting on structures adjacent to compaction fills. The monitoring program of a full-scale bridge abutment on soft soil supported by GECs and geogrid reinforced system is described, where field performance is monitored with pressure cells, electrical piezometers, inclinometers and settlement plates. Analytical and numerical analyses have been performed to help on interpreting experimental measurements. The collected database is interpreted to demonstrate that GEC can reduce by up to 50% the horizontal earth pressure over bridge border foundation piles when compared to values predicted for unreinforced ground and demonstrate that the work conformed to acceptable limits of behavior.     

A viability theory for digital businesses: Exploring the evolutionary changes of revenue mechanisms to support managerial decisions

The ongoing integration of Information Technology (IT) into various areas of our lives has led to a plethora of digital products and services. To survive competition in the long run, these offerings not only have to keep up with constant technological developments, but also have to adapt from a business point of view. Managers of these digital businesses have to especially focus on the design and evolution of their business’ revenue mechanisms to ensure the viability of their offerings. The related decisions are not trivial, as managers have to be aware of the relevant contextual factors and have to react quickly to changes in the environment. This paper proposes a viability theory for digital businesses described by 17 propositions that may guide managers in the design of revenue mechanisms and thereby support the evolution as well as the viability of a digital business.     

接地故障中和器全补偿技术及应用

目前世界上普遍应用的配电系统消弧线圈接地方式在一定程度上保证了系统的供电可靠性,但仍然存在接地残流较大和高阻型故障检测难等问题。GFN(接地故障全中和器)具有消除接地电流、准确定位故障点,以及提升供电稳定性和可靠性的作用。介绍了瑞典GFN接地故障全补偿技术的基本原理、功能特点、应用实例和功能扩展等。实用情况表明GFN接地故障全补偿技术可以较为成功地减少特殊瞬时故障。     

Effect of spin polarization of Ni(1 1 0) surface on Auger neutralization for grazing scattering of He ions

The survival of ions during grazing scattering of keV He⁺ ions from a clean Ni(1 1 0) surface is studied as function of target temperature. We observe ion fractions in the scattered beams of typically 10⁻³ which show a slight increase with temperature of the target surface. From computer simulations of projectile trajectories we attribute this enhancement for ion fractions to effects of thermal vibrations of lattice atoms on the survival of ions in their initial charge state. Based on concepts of Auger neutralization, we discuss the role of the spin polarization of target electrons on charge transfer. We do not find corresponding signatures in our data and conclude that in the present case of Ni(1 1 0) the spin polarization has to be small.     

Factors affecting length of herdlife in purebred and crossbred dairy cattle

The proportional hazards model with censoring was used to assess the effects of breeding value, disease, calving, size, and udder and lactation traits on length of herdlife of 3881 heifers in five herds. Data were recorded over 10 yr from three lines: a Holstein line, an Ayrshire-based line, and a crossbred line. Influences on survival were assessed from data collected at birth, 34, 50, and 82 wk, first freshening, and at 112 and 308 d postpartum. Median estimated herdlife (age at 50% culling) was 3.9 yr for animals alive at first freshening and increased to 4.3 yr for those that completed a first lactation (308 d postpartum). Herds differed greatly in the pattern of culling after freshening. Crossbred females had 21 wk longer median estimated herdlife than the mean of the purelines at 308 d postpartum. Individual milk yield was positively associated with longevity and had the greatest impact on length of herdlife. Abortion and fertility measured as days to last insemination were negatively associated with length of herdlife. Large heifers tended to have increased longevity. High feed intake postpartum was associated with reduced length of herdlife. Objective measures of conformation, which included measurements of the udder, were not important in determining herdlife.     

优化车门ECU功耗的新概念

<正>在现代汽车中,电子控制单元(ECU)的数量不断增长。现代电子零部件增加了许多功能可为驾驶员提供更多的信息和更舒适的环境,     

A genetic algorithm for the two-dimensional knapsack problem with rectangular pieces

Given a set of rectangular pieces and a rectangular container, the two-dimensional knapsack problem (2D-KP) consists of orthogonally packing a subset of the pieces within the container such that the sum of the values of the packed pieces is maximized. If the value of a piece is given by its area, the objective is to maximize the covered area of the container. A genetic algorithm (GA) is proposed addressing the guillotine case of the 2D-KP as well as the non-guillotine case. Moreover, an orientation constraint may optionally be taken into account and the given piece set may be constrained or unconstrained. The GA is subjected to an extensive test using well-known benchmark instances. Compared with recently published methods, the GA yields competitive results.     

Fullerene Single Crystals: Structure and Electronic Properties

Abstract

This work covers an advanced investigation of the single crystal growth process for fullerenic materials and the contribution of Raman and IR spectroscopy to the understanding of the fcc high temperature rotor phase and the low temperature sc ratchet phase of pristine C₆₀. In addition substantial research contributions to the understanding of alkali metal doped fullerenes are presented.

Alkali metal doped crystals are studied with particular attention to the line broadening in the superconducting A ₃C₆₀ phase and to the phases with stoichiometry A₁C₆₀. For the former electron-phonon coupling constants could be determined for all fivefold degenerated gerade modes and a total coupling strenght of λ = 0.90 was found. For the latter the different experimental conditions for obtaining the phase separated intermediate state or alternatively the orthorhombic polymeric state are analysed. Vibrational spectra for the polymeric state obtained from phototransformation and from mono alkali metal doping are found to be characteristically different, mainly with respect to the intensity of the Raman or IR response. Finally, research results obtained from the single crystals by various other techniques like thermal expansion or low frequency elastic deformation are summarized.     

微星X-Slim X340笔记本新“刀锋战士”

2009年1月召开的CES2009展上，微星（MSI）展出了令人惊艳的X—Slim系列笔记本产品。引起了业内的广泛关注。但是在接下来的两个月时间里。微星却一直对其遮遮掩掩，吊足了笔记本爱好者的胃口。，