Effectiveness of Ring Roads in Reducing Traffic Congestion in Cities for Long Run: Big Almaty Ring Road Case Study

It is common to increase road capacity by constructing ring roads to reduce traffic congestion in city areas, although this is often found to be ineffective in the long run. Accordingly, this study investigates various traffic congestion management approaches and their effectiveness in major cities, and explores an identical transport problem in Almaty, Kazakhstan: The Big Almaty Ring Road (BAKAD). Several case examples from the existing literature are examined in which various approaches were taken for managing traffic congestion problems, and these approaches are classified into three concepts. The first concept comprises heavy engineering measures such as ring road development, new road construction, expansion of existing roads, etc. Such measures can initially reduce traffic congestion, but often become ineffective with time due to the generation of induced traffic. Many cities have taken Push and Pull measures that ensure more efficient use of existing capacity and have initiated environmentally friendly alternative transportation modes such as decreased car usage; promotion of public transport, biking and walking; minimization of the necessity of people’s movement by changing urban land use patterns; and so on. These approaches have been found to be effective in providing sustainable transportation solutions and are classified as concept 2. Nevertheless, Push and Pull measures might not be enough for managing traffic congestion, and it might be necessary to increase the road capacity through heavy engineering measures, especially if the city experiences heavy transit traffic. This combined approach is categorized as concept 3. Consequently, the BAKAD project is examined under the umbrella of three concepts, and recommendations are provided based on the findings from the experience of different cities and interviews with experts from Almaty city. Both the results and recommendations developed are relevant for this specific case only, and are not necessarily transferable

Optimization of Mixture Parameter for Physical and Mechanical Properties of Reactive Powder Concrete under External Sulfate Attack using Taguchi Method

Reactive powder concrete (RPC) is defined as a cementitious composite material with an optimized size of granular constituents, very low water-to-binder ratio (w/b), pozzolanic materials like silica fume (SF), and discontinuous fiber reinforcement. RPC applications include bridge decks and girders, seismic columns, wind turbine towers, and pile foundations. Especially, a durable and robust RPC pile foundation with long service life is essential in building construction because continuous maintenance is impossible. Moreover, natural in-situ conditions such as water table, temperature, and sulfate concentration in soil to which the pile foundation is exposed are critical and related to deteriorating the pile foundation. Therefore, the Taguchi design of experiments (DOE) was used in this research to determine the optimal RPC mixture with beneficial characteristics against external sulfate attack (ESA). Mixture design parameters included steel fiber content (0, 1 and 2 %), w/b (0.16, 20 and 0.24), and SF content (15, 20 and 25 %). In contrast, environmental conditions of ESA exposure contained three different sodium sulfate (Na2SO4) concentrations (0.35, 1.05, and 3.15 M), cyclic and continuous exposure at normal temperature (20 °C), and continuous exposure at elevated temperatures (40 °C and 60 °C). The analytical and statistical investigation evaluated mass change, compressive strength, and modulus of rupture in RPC mixtures exposed to these conditions for 52 weeks. Test results show that cyclic exposure and increased solution temperature in ESA facilitate RPC damage. If measured after air drying, RPC mixtures subjected to cyclic ESA are especially susceptible to failure. Taguchi analysis indicated the optimum parameters\u27 level for mass change as: 0 % steel fiber, w/b = 0.16, and 20 % SF content; for the compressive strength: 2 % steel fiber, w/b = 0.24, and 20 % SF content; and, for modulus of rupture: 2 % steel fiber, w/b = 0.20, and 25 % SF content. In conclusion, RPC appears to be sustainable and durable material under different ESA exposure conditions

Observation and analysis of low temperature leak characteristics of the O-ring for hydrogen electric vehicles

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Dynamic complex network analysis of PM2.5 concentrations in the UK, using hierarchical directed graphs (V1.0.0)

The risk of a broad range of respiratory and heart diseases can be increased by widespread exposure to fine atmospheric particles on account of their capability to have a deep penetration into the blood streams and lung. Globally, studies conducted epidemiologically in Europe and elsewhere provided the evidence base indicating the major role of PM2.5 leading to more than four million deaths annually. Conventional approaches to simulate atmospheric transportation of particles having high dimensionality from both transport and chemical reaction process make exhaustive causal inference difficult. Alternative model reduction methods were adopted, specifically a data-driven directed graph representation, to deduce causal directionality and spatial embeddedness. An undirected correlation and a directed Granger causality network were established through utilizing PM2.5 concentrations in 14 United Kingdom cities for one year. To demonstrate both reduced-order cases, the United Kingdom was split up into two southern and northern connected city communities, with notable spatial embedding in summer and spring. It continued to reach stability to disturbances through the network trophic coherence parameter and by which winter was construed as the most considerable vulnerability. Thanks to our novel graph reduced modeling, we could represent high-dimensional knowledge in a causal inference and stability framework

MECHANICAL, SWELLING, AND THERMAL PROPERTIES OF GEOPOLYMER MIXTURE CONTAINING BASIC OXYGEN FURNACE SLAG AGGREGATES

Basic oxygen furnace slag (BOFS) is a waste product generated during steel production. The utilization of BOFS in construction applications is considerably limited because of its inherent characteristics leading to volumetric expansion behavior caused by the chemical reaction between free lime (f-CaO) and water. The main objective of this paper is to investigate the material properties of normal mortar and geopolymer mixtures that contain BOFS aggregates. Three different aggregates were used to compare their performance, including siliceous river sand, fresh BOFS aggregate (within 1-month age), and stockpiled (more than 5-year age) BOFS aggregate. Test methods included a compressive strength test, accelerated mortar bar expansion test, and thermal conductivity test. Test results revealed that (1) geopolymer mixtures containing BOFS aggregate had comparable compressive strength with mortar mixture with river sand, (2) geopolymer mixtures have very low volume expansion, (3) thermal conductivity of geopolymer mixtures having both river sand and BOFS was lower than normal cement mortar mixture containing river sand. Therefore, geopolymer technology seems a key solution for converting BOFS slag into valuable construction materials. Therefore, a geopolymer mixture containing BOFS aggregate can be used as an energy-saving material

A Synoptic- and Remote Sensing-based Analysis of a Severe Dust Storm Event over Central Asia

Published by [Verlag nicht ermittelbar], Taina

Cilostazol Decreases Ethanol-Mediated TNFalpha Expression in RAW264.7 Murine Macrophage and in Liver from Binge Drinking Mice

Alcoholic hepatitis is a leading cause of liver failure in which the increased production of tumor necrosis factor α (TNFα) plays a critical role in progression of alcoholic liver disease. In the present study, we investigated the effects of cilostazol, a selective inhibitor of type III phosphodiesterase on ethanol-mediated TNFα production in vitro and in vivo, and the effect of cilostazol was compared with that of pentoxifylline, which is currently used in clinical trial. RAW264.7 murine macrophages were pretreated with ethanol in the presence or absence of cilostazol then, stimulated with lipopolysacchride (LPS). Cilostazol significantly suppressed the level of LPS-stimulated TNFα mRNA and protein with a similar degree to that by pentoxifylline. Cilostazol increased the basal AMP-activated protein kinase (AMPK) activity as well as normalized the decreased AMPK by LPS. AICAR, an AMPK activator and db-cAMP also significantly decreased TNFα production in RAW264.7 cells, but cilostazol did not affect the levels of intracellular cAMP and reactive oxygen species (ROS) production. The in vivo effect of cilostazol was examined using ethanol binge drinking (6 g/kg) mice model. TNFα mRNA and protein decreased in liver from ethanol gavaged mice compared to that from control mice. Pretreatment of mice with cilostazol or pentoxifylline further reduced the TNFα production in liver. These results demonstrated that cilostazol effectively decrease the ethanol-mediated TNFα production both in murine macrophage and in liver from binge drinking mice and AMPK may be responsible for the inhibition of TNFα production by cilostazol