Pattern Of Taxes Research Articles

Econometric Analysis of Monthly Peak-Hour and Total Usage Patterns of Hong Kong’s Cross-Harbor Tunnels

As one of the most densely populated metropolises in the world, Hong Kong daily sees severe traffic delays at the Cross-Harbour Tunnel (CHT), though not at the Eastern Harbour Crossing (EHC) or the Western Harbour Crossing (WHC). In 2013, the Hong Kong Special Administrative Region (HKSAR) Government proposed raising the tolls of the publicly owned CHT and lowering those of the publicly owned EHC for nine vehicle types: private cars, motorcycles, taxis, three kinds of buses, and three kinds of goods vehicles. The privately owned WHC’s already high tolls, however, would remain unchanged. Using monthly usage and peak-hour usage data for January 2003 through June 2015, a Generalized Leontief demand system was estimated and found that private cars, motorcycles, and goods vehicles have price-sensitive tunnel usage patterns that are also time-dependent. The usage patterns of taxis and buses, which are public transportation vehicles, are totally price-insensitive. These findings suggest that the HKSAR Government’s proposed toll changes would reduce the CHT’s monthly usage by 7.4%–12.2%, and peak-hour usage by 5.0–16.8%. These usage reduction estimates suggest that a time-of-use (TOU) toll design can better manage CHT congestion than the current non-TOU design.

Low-temperature chemotaxis, halotaxis and chemohalotaxis by the psychrophilic marine bacterium Colwellia psychrerythraea 34H.

A variety of ecologically important processes are driven by bacterial motility and taxis, yet these basic bacterial behaviours remain understudied in cold habitats. Here, we present a series of experiments designed to test the chemotactic ability of the model marine psychrophilic bacterium Colwellia psychrerythraea 34H, when grown at optimal temperature and salinity (8°C, 35 ppt) or its original isolation conditions (-1°C, 35 ppt), towards serine and mannose at temperatures from -8°C to 27°C (above its upper growth temperature of 18°C), and at salinities of 15, 35 and 55 ppt (at 8°C and -1°C). Results indicate that C. psychrerythraea 34H is capable of chemotaxis at all temperatures tested, with strongest chemotaxis at the temperature at which it was first grown, whether 8°C or -1°C. This model marine psychrophile also showed significant halotaxis towards 15 and 55 ppt solutions, as well as strong substrate-specific chemohalotaxis. We suggest that such patterns of taxis may enable bacteria to colonize sea ice, position themselves optimally within its extremely cold, hypersaline and temporally fluctuating microenvironments, and respond to various chemical signals therein.