Aquaculture Parks in the Coastal Zone: A Review of Legal and Policy Issues in the Gulf of Mexico State Waters

The goal of this study is to apply industrial park concepts to the development of aquaculture parks in public waters. The objectives are to identify the permitting process, relevant agencies, and legislation needed to facilitate development. Gulf of Mexico states are surveyed: private parks exist in Florida, but no public parks have developed yet; plans for parks exist in Mississippi, but lack of funding prevents development; no regulations prohibit parks in Alabama, although none currently exist; Texas regulations hinder development of parks; and an experimental park has been proposed in Louisiana, but regulatory gaps have delayed permit issuance.     

Microscopic simulation of transit operations: policy studies with the MISTRANSIT application programming interface

Abstract

Microscopic traffic simulators are the most advanced tools for representing the movement of vehicles on a transport network. However, the energy spent in traffic microsimulation has been mainly oriented to cars. Little interest has been devoted to more sophisticated models for simulating transit systems. Commercial software has some options to incorporate the operation of transit vehicles, but they are insufficient to properly consider a real public transport system. This paper develops an Application Programming Interface, called MIcroscopic Simulation of TRANSIT (MISTRANSIT), using the commercial microsimulator PARAllel MICroscopic Simulation. MISTRANSIT makes advances in three ways: public transport vehicles can have new characteristics; passengers are incorporated and traced as individual objects; and specific models represent the interaction between passengers and vehicles at stops. This paper presents the modelling approach as well as various experiments to illustrate the feasibility of MISTRANSIT for studying policy operations of transit systems.     

The impact of marine engine operation and maintenance on emissions

This paper examines the role of marine engine maintenance in reducing pollution. It tests four marine diesel engines, one constructed prior to January 1, 2000 and three after 2000. This paper explains how the condition of an engine’s nozzles and faulty injection pressure significantly influence NO_x and CO emissions and describes both bench and onboard ship tests, on engines fitted with new or worn nozzles at different injection pressures. The tests showed that, when the engine constructed prior to 2000 operates under normal in-service conditions, the emissions are within limits, but, with a small fault in injection timing, the NO_x emissions exceed the limits. For the engines constructed after 2000, a fault in the maintenance of the nozzles increases the CO emissions to a high level.     

Temporal variations of water flow between the Venetian lagoon and the open sea

Long-term measurements of the water flow at three Venice Lagoon inlets with the bottom-mounted ADCPs show that the main part of the variance (>90%) is associated with the tidal variability. Semi-diurnal constituents (mainly M2 and S2) are responsible for about 80% of the flow variance. Phase-lag between the axial current and sea-level is on the order of 2 h for M2 and 4 h for the K1, the maximum inflow leading the sea-level maximum. Phase-difference of tidal flows between inlets shows that Chioggia leads both Malamocco and Lido, suggesting that tidal signal progresses northward, thus in the opposite direction of both the semi-diurnal and diurnal tidal signals in the open Adriatic currents. The sea-level slope between the open sea and the lagoon interior controls the inlet flow, which is due to the time lag being constant for all tidal constituents. It was shown that tidal oscillations at Punta Salute (lagoon interior) lag those in Lido by about 45 min. The pressure gradient due to the sea-level slope generates the flow acceleration. Only for large current speeds (>0.5 m/s), the bottom friction term becomes equally important as the local acceleration and the horizontal pressure gradient terms. Wind effects manifest as a remote forcing through Adriatic seiches at semi-diurnal and diurnal scales, and as a local forcing at very long time scales on the order of a month. This latter mechanism is limited to a winter period (November–January). Seiches are present over the entire year, being however, more energetic and frequent during autumn and winter.     

Modelling passengers,buses and stops in traffic microsimulation: review and extensions

In the last decade, significant research efforts and technology have been dedicated to the development of microsimulation tools for a better representation of traffic systems. As a result, several commercial packages appeared and they are used nowadays in the detailed modelling of different transportation systems and operations for specific project evaluations and local designs, mostly within the urban context. After reviewing the specialized literature, we realized that most of these microsimulation tools are oriented to the movement of cars, leaving the public transportation systems as a complement, just for a realistic representation of the transportation system as a whole, but always oriented to simulate cars. In this paper, the objective is to provide guidelines on how to incorporate the necessary entities and components for a proper simulation of public transport systems in a microsimulation environment. Thus, the different approaches to simulate transit systems at a microlevel are discussed, highlighting the necessity of including stops, passengers and transit vehicles explicitly as entities within the microsimulation environment, for modelling transfer operations, control strategies, etc. Several examples are then provided to quantify the impact of such representations, for different cases and potential simulation platforms. Copyright © 2010 John Wiley & Sons, Ltd.