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31.
32.
Giselle P. B. Samonte-Tan Alan T. White Mary Ann Tercero John Diviva Esperanza Tabara Ciemon Caballes 《Coastal management》2013,41(2-3):319-338
This article provides results on the net benefits generated from the natural resources in the Bohol Marine Triangle (BMT) in the Philippines. The BMT spans over 112,000 ha and its coastal ecosystems are rich in biodiversity and provide economic opportunities to the coastal communities. With a 10% discount rate, the accumulated total net benefits for the BMT resources over a 10-year period is US$11.54 million. Tourism and the municipal fisheries are the most important direct use values of the coastal and marine resources of the BMT accounting for 44% and 39% of the total net benefits. Annual revenues attributed to ecosystems were as follows: coral reefs, US$1.26 million; beach/intertidal area, US$1.12 million; marine waters, US$646,501; mangrove, US$239,561; and seagrass, US$105,990. The large market values indicate the dependence of the local community on the BMT coastal and marine resources. In the same way, non-market values show the important life-support functions of coastal and marine ecosystems. The net benefits reflect the magnitude of potential losses due to improper management of coastal and marine resources in the BMT. This valuation highlights the importance of the coastal services to the BMT economy and draws attention to the benefits the local stakeholders derive from BMT coastal resources. Policy measures can now take into account these values to justify a sufficient investment in coastal management efforts to sustain the flow of coastal services in the interest of current and future generations. 相似文献
33.
B. N. Metaxas 《Maritime Policy and Management》2013,40(3):162-177
The purpose of this article is to formulate the problem, to assess its magnitude, and at the same time to suggest the areas that must be investigated before any practical policy recommendations can be made. 相似文献
34.
D. B. Sonawane K. Narayan V. S. Rao S. C. Subramanian 《International Journal of Automotive Technology》2011,12(5):697-704
Most commercial vehicles such as buses and trucks use an air brake system, often equipped with an S-cam drum brake, to reduce
their speed and/or to stop. With a drum brake system, the clearance between the brake shoe/pad and the brake drum may increase
because of various reasons such as wearing of the brake shoe and/or brake drum and drum expansion caused by high heat generation
during the braking process. Hence, to ensure proper functioning of the brake system, it is essential that the clearance between
the brake shoe and the brake drum is monitored. In this paper, we present a mathematical model for the mechanical subsystem
of the air brake system that can be used to monitor this clearance. This mathematical model correlates the push rod stroke
transients and the brake chamber pressure transients. A kinematic analysis and a dynamic analysis of the mechanical subsystem
of the air brake system were performed, and the results are corroborated with experimental data. 相似文献
35.
36.
Abstract Artificial reefs have been used extensively in coastal waters to attract and enhance recreational fishery resources. In the United States, they have been traditionally built from “materials of opportunity”; using limited budgets. This paper explores some past planning philosophies and presents a recent artificial reef deployment case that demonstrates a lack of sensitivity to local and regional recreational demand. A systems framework is developed to guide future planning efforts in artificial reef development. The framework is intended to integrate previously fragmented knowledge and to demonstrate the interdisciplinary nature of artificial reef planning. Emphasis is given to advance planning, user dimensions, and the integral issue of reef access. 相似文献
37.
Margarida C. Coelho Marco B. Luzia 《Transportation Research Part D: Transport and Environment》2010,15(8):443-450
This paper analyzes the energetic performance of the hybrid Lexus RX 400h, through on-board measurements. Several speed profiles were analyzed, for three driving types, successive stop and go cycles, three speed profiles, crossing an electronic toll collection booth, and a roundabout. In stop and go situations the internal combustion engine did not work (the torque needed to impulse the vehicle in the stop and go situations was only supported by the electric engines), as well as in the situations of constant low speeds (50 or 60 km h?1). The auxiliary support given by the electric engines in the accelerations, as well as the importance of the energy regeneration system on the batteries’ load recovery is also demonstrated. When compared with similar conventional vehicles, the Lexus RX 400h has lower combined energy consumption between 1.2% and 60%. 相似文献
38.
Development of hot stamped center pillar using form die with channel type indirect blank holder 总被引:1,自引:0,他引:1
H. S. Choi B. M. Kim K. J. Nam S. Y. Ha S. H. Cha C. G. Kang 《International Journal of Automotive Technology》2011,12(6):887-894
The hot stamping process has been used in the automotive industry to reduce the weight of the body-in-white and to increase
passenger safety via improved crashworthiness. However, defects such as fracture and wrinkle occur when hot stamping is performed
using a conventional drawing or forming method. In this study, a channel-type indirect blank holder (CIBH) is proposed to
develop a high-strength center pillar in form-type hot stamping, so that the aforementioned drawbacks are overcome. This type
of blank holder plays an important role in reducing severe wrinkling at the flange; such wrinkling leads to folding after
the completion of form-type hot-stamping. First, we investigated the effect of the channel shape on the indirect blank holding
force by using a simplified two-dimensional plane-strain stamping process. Second, we selected the slope angle and corner
radius of the channel as the main shape parameters by finite element analysis and artificial neural network (ANN). It is known
that fracture at the hot formed wall and wrinkle at the flange are significantly affected by the slope angle of the channel,
and the appropriate value for eliminating fracture and wrinkle is determined to be 99°. By performing hot stamping using a
form die with the selected channel, we can manufacture a high-strength center pillar without wrinkle and fracture. 相似文献
39.
J. Ejsmont S. Taryma G. Ronowski B. Swieczko-Zurek 《International Journal of Automotive Technology》2016,17(2):237-244
Tyre load and inflation pressure are important factors controlling rolling resistance of road vehicles. The article presents results obtained in the Technical University of Gdańsk during laboratory and road measurements of different car tyres rolling on different pavements. The knowledge of rolling resistance characteristics is important for modelling car dynamics as well as fuel consumption. It is also necessary to establish proper test conditions in the future standardized on-road method of measuring rolling resistance. The results indicate that while an increase of load always leads to the increase of rolling resistance force, the influence on Coefficient of Rolling Resistance is more complicated and unpredictable. They also indicate that tyres with high rolling resistance are more sensitive to inflation pressure changes than low rolling resistance tyres. 相似文献
40.
This paper offers novel insights to the design and implementation of an innovative state-of-charge (SOC) estimator for the lithium-ion (Li-Ion) series battery pack. The most interesting feature of this approach is that it can utilize information from each filtered terminal voltage of the Li-Ion cells connected in series for SOC estimation of the battery pack. Without actual sensing each discharging/charging current (DCC) applied to the Li-Ion cells, it is possible to extract each DCC estimation from the corresponding filtered terminal voltages with an equivalent electrical circuit model (EECM) identification of all Li-Ion cells in the battery pack. There are two advantages to SOC estimation of the battery pack with this approach. First, the proposal can be implemented simply and effectively, reducing the computational steps required for SOC estimation. By reducing computational steps, the proposal is expected to be more cost-effective. Second, the approach guarantees an improved SOC performance, even if the battery pack results in inevitable cell-to-cell variation among Li-Ion cells. Accordingly, there are fewer differences to previously estimated DCCs among Li-Ion cells. Specifically, all values from the estimated DCCs are properly compensated for by simultaneous parameter modification according to each cell’s electrochemical characteristics. Experimental results clearly demonstrate that our DCC sensorless SOC estimator provides robust SOC performance for the battery pack. This approach considered an experimental battery pack (12S1P) connected in series using 2.6 Ah LiCoO2 cells produced by Samsung SDI. 相似文献