Where is the "Frugal Olympics"?

The one-year countdown to the 2008 Beijing Olympics and its media fanfare have come and gone, leaving behind persistent calls for an "economical and practical" Olympics to counteract perceived waste and excess in preparing for the Games. Increasingly, in the past few years, such sentiments have found their way onto the Internet, in blogs, discussion forums and local papers as a full accounting of the spending on various Olympic constructions and events has yet to be fully disclosed to the public.Similar to the open letter "OneWorld,One Dream and Universal Human Rights" from 40 Chinese academics, writers and human rights activists, these sentiments against an extravagant and wasteful Olympics provide another perspective often hidden from themedia glare aimed at festivities and publicity campaigns. This HRIC Issues Brief provides a sample of the range and diversity of these critical views on the Beijing Olympic Games expressed by Chinese Netizens on general blogs and Internet discussion and news forums

Supersymmetric Spin Networks and Quantum Supergravity

We define supersymmetric spin networks, which provide a complete set of gauge invariant states for supergravity and supersymmetric gauge theories. The particular case of Osp(1/2) is studied in detail and applied to the non-perturbative quantization of supergravity. The supersymmetric extension of the area operator is defined and partly diagonalized. The spectrum is discrete as in quantum general relativity, and the two cases could be distinguished by measurements of quantum geometry.Comment: 21 pages, LaTex, 22 figures, typos corrected and references complete

User behaviors toward mobile video adoption in Taiwan: A qualitative study

This study was designed to examine users' usage behaviors toward mobile video adoption in Taiwan. A modified UTAUT (Unified Theory of Acceptance and Use of Technology) model was designed to be the theory basis to develop questionnaires and open-ended questions. Data were gathered from six participants from iOS and Android users, two experts, and one focus group with five members. The study was conducted from February to April, 2011. The findings in this study supported those in the literature review: Effort Expectancy and Perceived Playfulness factors had positive influence to users' usage behaviors. Facilitating Conditions and Performance expectancy also had positive effect to users' usage behaviors toward mobile video app adoption. Network quality issue was the concern and should be added in the model. Moreover, several implications and suggestions for mobile video app adoption were discussed in the study. --mobile video,Unified Theory of Acceptance and Use of Technology model (UTAUT),mobile video adoption,Taiwan

Experimental investigation on cold-formed steel beams under pure bending

This paper presents the flexural behaviour of cold-formed double lipped channels beams under pure bending action. Two channel sections are bolted back-to-back to form an I-shape structural beam member. A series of six experiment tests were carried out on beam specimens DC200 and DC250, each with 200 mm depth and 250 mm depth respectively. The thickness of beam section is 2 mm and the design yield strength is 350 N/mm2. All beams failed at local buckling at top-flange due to lateral instability of the cold-formed steel structural members. The moment resistance for DC200 is 17.87 kNm and DC250 is 31.53 kNm. The experimental results are compared to theoretical resistance prediction based on British Standard and Eurocode. The comparison showed that the experimental moment capacity is lower than the theoretical bending moment resistance but higher than theoretical buckling moment resistance from Eurocode. This showed that a better agreement is achieved between experimental data and Eurocode buckling moment resistance for cold-formed steel beam under pure bending

Threshold Regression for Survival Analysis: Modeling Event Times by a Stochastic Process Reaching a Boundary

Many researchers have investigated first hitting times as models for survival data. First hitting times arise naturally in many types of stochastic processes, ranging from Wiener processes to Markov chains. In a survival context, the state of the underlying process represents the strength of an item or the health of an individual. The item fails or the individual experiences a clinical endpoint when the process reaches an adverse threshold state for the first time. The time scale can be calendar time or some other operational measure of degradation or disease progression. In many applications, the process is latent (i.e., unobservable). Threshold regression refers to first-hitting-time models with regression structures that accommodate covariate data. The parameters of the process, threshold state and time scale may depend on the covariates. This paper reviews aspects of this topic and discusses fruitful avenues for future research.Comment: Published at http://dx.doi.org/10.1214/088342306000000330 in the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

Reduction of the radar cross section of arbitrarily shaped cavity structures

The problem of the reduction of the radar cross section (RCS) of open-ended cavities was studied. The issues investigated were reduction through lossy coating materials on the inner cavity wall and reduction through shaping of the cavity. A method was presented to calculate the RCS of any arbitrarily shaped structure in order to study the shaping problem. The limitations of this method were also addressed. The modal attenuation was studied in a multilayered coated waveguide. It was shown that by employing two layers of coating, it was possible to achieve an increase in both the magnitude of attenuation and the frequency band of effectiveness. The numerical method used in finding the roots of the characteristic equation breaks down when the coating thickness is very lossy and large in terms of wavelength. A new method of computing the RCS of an arbitrary cavity was applied to study the effects of longitudinal bending on RCS reduction. The ray and modal descriptions for the fields in a parallel plate waveguide were compared. To extend the range of validity of the Shooting and Bouncing Ray (SBR) method, the simple ray picture must be modified to account for the beam blurring

An Optimal Trade-off between Content Freshness and Refresh Cost

Caching is an effective mechanism for reducing bandwidth usage and alleviating server load. However, the use of caching entails a compromise between content freshness and refresh cost. An excessive refresh allows a high degree of content freshness at a greater cost of system resource. Conversely, a deficient refresh inhibits content freshness but saves the cost of resource usages. To address the freshness-cost problem, we formulate the refresh scheduling problem with a generic cost model and use this cost model to determine an optimal refresh frequency that gives the best tradeoff between refresh cost and content freshness. We prove the existence and uniqueness of an optimal refresh frequency under the assumptions that the arrival of content update is Poisson and the age-related cost monotonically increases with decreasing freshness. In addition, we provide an analytic comparison of system performance under fixed refresh scheduling and random refresh scheduling, showing that with the same average refresh frequency two refresh schedulings are mathematically equivalent in terms of the long-run average cost

Preparation and Characterization of Bi2-O3-M2o5 (M =P,As, V) Oxide Ion Conductors

Bi203-M205, M = P, AS, V systems and related materials were prepared by solid state reactions. The phase purity of the materials was determined by X-ray diffraction (XRD). Further characterization using ac impedance spectroscopy and differential thermal analysis (DTA) were carried out on single phase materials. Besides, inductively coupled plasma-atomic emission spectrometry (ICP-AES), density measurement, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier-transform i n h e d (FT-IR) spectroscopy and Rarnan spectroscopy were also performed on selected materials. The crystal system and space group of the single phase materials were determined. Two narrow solid solution series were formed in xBi2O3-P205: 5.5 I x I 6 and 7 I x 5 7.25. In DTA study, a phase transition was clearly seen in Bi7P013 and Bi~gP40~a~t .-856 0°C.XRD shows that single phase materials were formed in xBi203-As205 binary system when x = 5, 5.5, 5.667, 5.75, 6 and 7. Among these, materials in the composition range of 5 5 x 5 6.25 appeared to be solid solutions. Attempts to synthesize materials of composition of xBi203-As2051, I x I 4 were unsuccesshl. Single phase materials were formed in xBi203-V205 binary system, 5 I x I 6 and x = 7. A phase transition was observed in Bi17V303a3n d Bi23V404.5 at -180°C. However, its origin is unknown. Materials of composition xBi203-M205, 5.5 I x I 6 (M = P) and 5 I x I 6 (M = As, V) are refined in triclinic symmetry with space group of P-I. Meanwhile, monoclinic symmetry was found in materials where x = 7, 7.25 (M = P) and x = 7(M = As, V). The XRD and IR patterns of both series of xBi203-As205, 5 I x I 6.25 and xBi203-V205, 5.5 5 x I 6 solid solutions are very similar since these materials are isostructural. Generally, lattice parameters, volumes and densities of the materials in xBi203-M205 system, M = P, As, V increased with the increase of Bi content. A complete solid solution series was formed in the Bi22P4043-Bi22As4043, Bi22P4043- Bi22V4043, Bi22As4043-Bi22V4043, Bi23P40~.5-Bi23As4044.5, Bi23P404.5-Bi23V4044.5, Bi23A~4044.5-Bi23V4044B.5i1, 2P2023-Bi 12A~2023, Bi 12P2023-Bi12V2023, Bi12As20~- Bi12V202a3n d Bi7AsO13-Bi7V013s ystems. In Bi7PO13-Bi7AsO1a3n d Bi7PO13-Bi7V013 systems a two-phase region was seen. All the single phase materials studied above appeared to be oxide-ion conductors. Conductivity increased with increasing vanadium content, followed by arsenic and phosphorus. Among the materials prepared, the highest conductivity is obtained in Bi23V4044.5w ith a 0 value of 1.34 x lo4 ohm" cm" at 300°C. In an attempt to optimize oxide ion conductivity, chemical doping using PbO, S@O3)2, A1203, Ga203, La203, Fe203 etc. was carried out in selected materials, resulting in the formation of limited solid solutions. These materials, however, exhibit conductivity slightly lower than that of the parent materials. Ball milling process has been carried out in the preparation of Bi23V4044.5a nd Bi14P06 in addition to manual grinding prior to fihg of the samples. In ball milling process, high-density, fine-grained powders with uniform grain-size distribution were obtained, resulting in an increase in conductivity and dielectric constants. Sillenite compounds in the Bi203-P205b inary system with Bi:P ratios of 13:l to 16:1 have been synthesized and found to be solid solutions. Substitution of P by V and As in the material where Bi:P = 14:l results in partial and complete solid solutions, respectively. Enhancement in conductivity was observed in these solid solutions with Vdoped materials exhibiting the highest conductivity. Substitution of P by elements such as pb2+, s?+,~ 1 ~~+a,~ ~+e,~ si+4+,,~ e ~an+d ,~ ile~ads +to f ormation of limited solid solutions. Most of these materials have conductivity similar to or slightly higher than that of the parent compound. These materials appeared to be predominantly oxide ion conductors especially at temperatures above 800°C where y + 6' polymorphic transformation occurred