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191.
校秋蓉 《西安交通大学学报(英文版)》1995,(2)
REGULATIONOFTHEINTERFERON-INDUCIBLEPROTEINKINASEPKRAND2'5'OLIGOADENYLATESYNTHETASEBYACATALYTICALLYINACTIVEPKR MUTANTTHROUGH C... 相似文献
192.
校秋蓉 《西安交通大学学报(英文版)》1995,(2)
REVERSALOFTHEDOUBLE-STRANDED-RNA-INDUCEDINHIBITIONOFPROTEINSYNTHESISBYACATALYTICALLYINACTIVEMUTANTOFTHEPROTEIN KINASEPKRTyson... 相似文献
193.
In 2006, a review of maritime accidents found that non-technical skills (NTSs) are the single largest contributing factor towards such incidents. NTSs are composed of both interpersonal and cognitive elements. These include things such as situational awareness, teamwork, decision making, leadership, management and communication skills. In a crisis situation, good NTSs allow a deck officer to quickly recognise that a problem exists and then harness the resources that are at their disposal to safely and efficiently bring the situation back under control. This paper has two aims. The first is to develop a methodology which will enable educators to quantitatively assess the impact of Maritime and Coastguard Agency (MCA)-approved Human Element, Leadership and Management (HELM) training on deck officer’s NTSs with a view to identifying further training requirements. The second is to determine whether the HELM training provided to develop the NTSs of trainee deck officers is fit for purpose. To achieve these aims, a three-phase approach was adopted. Initially, a taxonomy for deck officer’s NTSs is established, behavioural markers are identified and the relative importance of each attribute is calculated using the analytical hierarchy process (AHP). Subsequently, a set of scenarios were identified for the assessment of deck officer’s NTSs in a ship bridge simulator environment. A random selection of students that have completed the Chief Mate (CM) programme was performed, and data regarding their NTS-related performance in the scenarios was collected. Finally, the collected data was fed into the evidential reasoning (ER) algorithm, utility values were produced and, having established these values, the effectiveness of the HELM training that the students have received was then evaluated. 相似文献
194.
ABSTRACTThe main goal of this study was to assess the impact of the economic crisis on the productivity growth of the Spanish Port System (SPS). The Malmquist Productivity Index (MPI) was estimated for the 28 Port Authorities of the SPS, for a ‘non-crisis period’ (2005–2008) and a ‘crisis period’ (2008–2011). From a policy perspective, the MPI is a very useful approach for assessing the productivity change because it can be decomposed into the catching-up index and the frontier productivity index. The results showed that the economic crisis did not impact all of the Spanish Port Authorities equally. Some Port Authorities presented higher productivity growth during the crisis period than in the non-crisis period. Further analysis by the Mann–Whitney test revealed that Port Authority investments and productivity growth were statistically related. Information provided by this study may be very useful for stakeholders and decision-makers, in terms of long-term strategic planning and improving the competitiveness of the SPS. The findings illustrate that the economic crisis should not be seen as an international tragedy, but as an opportunity to adapt port traffics and installations to new needs and market demands. 相似文献
195.
The U.S. Army Corps of Engineers administers the only nationwide regulatory program that controls development activities in U.S. waters and wetlands. This article examines the statutory authorities, jurisdictional limitations, and evolution of the current Corps regulations, which express a strong policy to protect wetlands, estuaries, and tidal waters from unnecessary dredging, filling, or other alteration. The article explains the organization and procedures of the U.S. Army Corps of Engineers and examines in detail several precedential permit cases which have developed and implemented the Corps “wetlands policy.”; The article also evaluates current and potential policies underlying the regulatory efforts of the Corps of Engineers. 相似文献
196.
van der Kolk N. J. Akkerman I. Keuning J. A. Huijsmans R. H. M. 《Journal of Marine Science and Technology》2021,26(4):1126-1143
Journal of Marine Science and Technology - Wind propulsion for commercial ships has been identified as a key component in the energy transition for the maritime industry. The sailing hybrid ship... 相似文献
197.
The U.S. national beach nourishment experience is summarized for the East Coast barrier islands, the Gulf of Mexico, New England, and the Great Lakes. A total of 1,305 nourishment episodes on 382 beaches are recorded at a total estimated cost of approximately $1.4 billion ($2.5 billion in 1996 dollars). In terms of both volume and costs, nourishment has been the most extensive by far on the East Coast barrier islands. Depending on the region, between 65% and 85% of all nourishment projects have a federal funding component. Annual expenditures and sand volumes for beach nourishment are increasing, especially on East Coast barriers. At present, total annual national beach nourishment costs (excluding the Pacific Coast) are on the order of $100 million per year. The cost per cubic yard of nourishment sand as expressed in 1996 dollars has remained more or less constant over time. Additionally, the volumes of sand needed for subsequent nourishment episodes on individual beaches do not decrease, despite contrary assumptions in the shoreface-profile-ofequilibrium concept that subsequent nourishment volumes should diminish. In light of the historical experience of beach nourishment identified in this study, individual state and local coastal communities should reevaluate their plans for future beach nourishment programs. The complete listing of all the data on nourished beaches from this survey is available at www.geo.duke.edu/Research/psds/psds.htm 相似文献
198.
The acoustic analogy represents a powerful and versatile approach, able to numerically predict the noise generated by a body moving in a fluid. It is widely used to provide essential indications about the aeroacoustic behavior of aircraft and helicopters (even at a design stage) and, eventually, to pursue effective strategies aimed at desirable reduction and/or control of noise. Nevertheless, applications in the area of hydroacoustics and in the prediction of ship underwater noise are very rare. In this paper, the potential of the acoustic analogy is directly tested on a large ferry, for which a measurement campaign at sea was performed. In spite of the complexity of the tested configuration [the ship mounts two contracted and loaded tip (CLT) propellers located ahead of two rudders, and its hull is characterized by a rather elongated skeg] and the many variables not taken into account in the numerical simulation (such as the contribution from machinery noise and the probable occurrence of tip vortex cavitation), the agreement between the measured and computed noise spectra is quite satisfactory. The analysis suggests many interesting features of the ship hydroacoustic field: the dominant role played by nonlinear sources far from the body and the relevance of scattering effects from the hull surface. Furthermore, the scattered pressure seems to contribute to alter the frequency content of the resulting signatures with respect to the blade passage frequencies. Finally, an overview of future developments and applications of this numerical approach for marine/maritime problems is presented. 相似文献
199.
P. Sundarraman S. K. Saha N. J. Vasa R. Baskaran V. Sunilkumar K. Raghavendra 《International Journal of Automotive Technology》2012,13(2):193-203
The Fuel-Injection Pump (FIP) used in diesel engine has a higher-pair cam-mechanism to pressurize the fuel for injection.
This paper proposes a methodology to model FIP from a multibody Dynamics (MBD) perspective. The results from the model include
the temporal behavior of driving torque, contact Hertz stress and reaction forces at various joints. The model helps the designer
to assess the effect of various cam profiles, link parameters and other design variables. It is necessary that these parameters
be optimized for future high pressure applications. For this purpose, a cam-mechanism with offset follower axis is analysed.
Decoupled Natural Orthogonal Complement (DeNOC) matrices based algorithm is used to model FIP without and with offset cam-mechanism.
The study shows that, the offset cam-mechanism allows reduction in the side-thrust, reaction forces, and the contact Hertz
stress acting on the cam-follower interface. As a typical case, for an FIP working around a pressure value of 600 bar, an
optimum offset value is found to be 9.5 mm and it shows a reduction of about 45% in side thrust values. To validate the modeling
approach, experimental studies are performed on pump without and with offset cam-mechanism. Experimental results are in qualitative
agreement with the theoretical model results. 相似文献
200.
The impacts of the tsunami in 2004 on the reefs in Surin Marine National Park, Thailand, varied with the location and exposure of the reefs. Channel areas between islands were severely damaged. Areas with steep reef slopes were damaged by sand slides or coral collapse more than areas with low slopes. Massive, sub-massive, and encrusting corals were more resistant and resilient to the direct impact of the tsunami than branching, tabulate, and foliose life forms whereas the latter were more tolerant of temporary coverage by sand. Sub-massive corals were the most tolerant overall and survived sand coverage, breakage, and overturning. Live coral cover measured three months after the tsunami was significantly greater than immediately post-tsunami as broken, moved, or sand-covered corals, recorded as impacted in the initial survey, had survived and were regenerating. Low turbidity, lack of pollution, and mild currents possibly contributed to rapid recovery and limited long-term effects of the tsunami. Impact assessment shortly after a major disturbance may give an initial measure of damage but subsequent surveys must be undertaken to identify long-term effects. Understanding patterns of reef damage can help to formulate reef zoning and protection strategies in response to catastrophic events, but also in advance of such events to improve likely resilience of the marine park to disturbance. 相似文献