Network distribution capacity and content-pipe gap

The growth of video content and diversification of content-sharing methods in the Internet lead to an exciting range of new problems in networking, communications, and signal processing. They range from fundamental theory and analytic models to practical design and industry deployment. This informal note briefly discusses some of the opportunities arising out of the “content-pipe” gap and presents some of the fundamental problems in distributing content over a network

Seasonally Frozen Soil Effects on the Seismic Performance of Highway Bridges

INE/AUTC 12.0

Mobile Communications Industry Scenarios and Strategic Implications for Network Equipment Vendors

Mobile infrastructure markets have changed dramatically during the past years. The industry is experiencing a shift from traditional large-scale, hardware-driven system roll-outs to software and services -driven business models. Also, the telecommunications and internet worlds are colliding in both mobile infrastructure and services domains requiring established network equipment vendors and mobile operators to transform and adapt to the new business environment. This paper utilizes Schoemaker's scenario planning process to reveal critical uncertain elements shaping the future of the industry. Four possible scenarios representing different value systems between industry's key stakeholders are created. After this, five strategic options with differing risk and cost factors for established network equipment vendors are discussed in order to aid firm's strategic planning process. --

Improving the resilience of post-disaster water distribution systems using a dynamic optimization framework

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Improving the resilience of water distribution systems (WDSs) to handle natural disasters (e.g., earthquakes) is a critical step towards sustainable urban water management. This requires the water utility to be able to respond quickly to such disaster events and in an organized manner, to prioritize the use of available resources to restore service rapidly whilst minimizing the negative impacts. Many methods have been developed to evaluate the WDS resilience, but few efforts are made so far to improve resilience of a post-disaster WDS through identifying optimal sequencing of recovery actions. To address this gap, a new dynamic optimization framework is proposed here where the resilience of a post-disaster WDS is evaluated using six different metrics. A tailored Genetic Algorithm is developed to solve the complex optimization problem driven by these metrics. The proposed framework is demonstrated using a real-world WDS with 6,064 pipes. Results obtained show that the proposed framework successfully identifies near-optimal sequencing of recovery actions for this complex WDS. The gained insights, conditional on the specific attributes of the case study, include: (i) the near-optimal sequencing of recovery strategy heavily depends on the damage properties of the WDS, (ii) replacements of damaged elements tend to be scheduled at the intermediate-late stages of the recovery process due to their long operation time, and (iii) interventions to damaged pipe elements near critical facilities (e.g., hospitals) should not be necessarily the first priority to recover due to complex hydraulic interactions within the WDS

TAO Conceptual Design Report: A Precision Measurement of the Reactor Antineutrino Spectrum with Sub-percent Energy Resolution

The Taishan Antineutrino Observatory (TAO, also known as JUNO-TAO) is a satellite experiment of the Jiangmen Underground Neutrino Observatory (JUNO). A ton-level liquid scintillator detector will be placed at about 30 m from a core of the Taishan Nuclear Power Plant. The reactor antineutrino spectrum will be measured with sub-percent energy resolution, to provide a reference spectrum for future reactor neutrino experiments, and to provide a benchmark measurement to test nuclear databases. A spherical acrylic vessel containing 2.8 ton gadolinium-doped liquid scintillator will be viewed by 10 m^2 Silicon Photomultipliers (SiPMs) of >50% photon detection efficiency with almost full coverage. The photoelectron yield is about 4500 per MeV, an order higher than any existing large-scale liquid scintillator detectors. The detector operates at -50 degree C to lower the dark noise of SiPMs to an acceptable level. The detector will measure about 2000 reactor antineutrinos per day, and is designed to be well shielded from cosmogenic backgrounds and ambient radioactivities to have about 10% background-to-signal ratio. The experiment is expected to start operation in 2022

Meggondolások egy infrastruktúra-orientált gazdaságfejlesztési stratégia előnyeiről és hátrányairól | Considerations on advantages and drawbacks of an infrastructure-oriented development strategy

Az infrastruktúra-orientált gazdaságfejlesztési stratégia előnyeivel és hátrányaival foglalkozó dolgozat kiindulásnak tekinti, hogy nem elegendő egyetlen, legjobbnak remélt politikai stratégia biztos bekövetkezésének a bázisára építeni a gazdaságpolitikát. A figyelembe vett öt lehetséges forgatókönyv közül a három pozitív kimenetelű szcenárióhoz igen hasonló, az ország belső, térségi fejlődését elősegítő, a centralizált infrastrukturális szerkezeteket oldani igyekvő átstrukturálódással jellemezhető hálózatok tartoznak. Ezzel szemben az elkerülni kívánt forgatókönyveket éppen a meglévő, hierarchikus, centralizált infrastruktúrahálózati szerkezetek megerősítése segítené elő. Ebben a helyzetben nagyon határozottan foglal állást a dolgozat amellett, hogy nem elegendő az infrastruktúra-orientáció általában való hangoztatása, mert míg az átstrukturálódást elősegítő hálózatok kiépülésére sürgető szükség van, addig más, ezzel tartalmilag ellentétes, struktúramerevítő hálózatok kiépülése kifejezetten kártékony lenne. A politikai forgatókönyvek segítségével levezetett megkülönböztetéssel összhangban van az a tapasztalat, ami a jelenleg működő nagy európai szerkezetek - közlekedési, gáz és elektromos hálózatok - elemzése és fejlesztési tendenciáinak vizsgálata nyomán nyerhető. A megfelelő lokális ellátottságot biztosítani képes disztributív hálózatok kellő alapot nyújtanak, bázisul szolgálnak ahhoz, hogy a nagyobb, magisztrális hálózatok csomóponti hatásainak is a pozitívumai érintsék az adott térséget. Ezzel szemben a fejletlen, ellátatlan térségekben a magisztrális hálózatok könnyen szigetszerű, harmadik világ típusú, a fejlődést inkább torzító, mint segítő hatást váltanak ki, a lemaradás felszámolása helyett annak tartósítását segítik elő. Csak az ezt figyelembe vevő, árnyalt, szelektív módon bevezetett infrastruktúra-orientált gazdaságpolitika szolgálhat kedvező fejlesztési alternatívaként az ország számára. | According to the author, different international political scenarios may be realized, so it is unfounded to plan the future only accepting the possibility seeming most favourable to us. It is worthwhile to think about, which political scenario is comparible with which infrastructure-development version. It is not indifferent at all, what projects we support under the slogan „more infrastructure". There are infrastructures whose establishment would be expressly harmful for the country. This can be proved by arguments both in- and outside the economy

An investigation of condensation heat transfer in a closed tube containing a soluble noncondensable gas

A more exact one-dimensional condensation heat transfer model for insoluble gases was developed and compared with experimental data. Modifications to this model to accommodate soluble gas behavior were also accomplished, and the effects on gas front behavior demonstrated. Analytical models for condensation heat transfer are documented, and an optical method used for measuring gas concentration profiles is outlined. Experimental data is then presented and interpreted

Travelling-wave thermoacoustic electricity generator using an ultra-compliant alternator for utilization of low-grade thermal energy

This paper proposes a novel concept of a travelling-wave thermoacoustic electricity generator, which employs a looped-tube travelling-wave thermoacoustic engine to convert thermal energy into acoustic power, an ultra-compliant alternator within the engine loop to extract and convert the engine acoustic power to electricity and an acoustic stub matching technique to match the alternator to the engine. In addition, a carefully designed cold heat exchanger acts as a phase shifting inertance to improve the performance. A simple model has been developed to capture and demonstrate the physics of this new concept, while the whole system has been investigated in detail numerically by using a specialized design tool DeltaEC. Based on the current concept, a prototype has been designed, constructed and tested. It uses atmospheric air as the working fluid, a commercially available audio loudspeaker as the electro-dynamic transducer, and inexpensive standard parts as the acoustic resonator. The experimental results have verified the simplified model and the numerical simulations of the practical build. The small-scale inexpensive prototype generator produced 11.6 W of electrical power, which shows the potential for developing cheap thermoacoustic electricity generators for energy recovery from waste heat sources. It is concluded that such concept could be very attractive provided that inexpensive ultra-compliant alternators based on the standard technology used in audio loudspeakers could be developed. Finally, some guidelines have been discussed and proposed for developing such alternators