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191.
R. C. Zhao P. K. Wong Z. C. Xie J. Zhao 《International Journal of Automotive Technology》2017,18(2):279-292
In this paper, a novel spacing control law is developed for vehicles with adaptive cruise control (ACC) systems to perform spacing control mode. Rather than establishing a steady-state following distance behind a newly encountered vehicle to avoid collision, the proposed spacing control law based on model predictive control (MPC) further considers fuel economy and ride comfort. Firstly, a hierarchical control architecture is utilized in which a lower controller compensates for nonlinear longitudinal vehicle dynamics and enables to track the desired acceleration. The upper controller based on the proposed spacing control law is designed to compute the desired acceleration to maintain the control objectives. Moreover, the control objectives are then formulated into the model predictive control problem using acceleration and jerk limits as constrains. Furthermore, due to the complex driving conditions during in the transitional state, the traditional model predictive control algorithm with constant weight matrix cannot meet the requirement of improvement in the fuel economy and ride comfort. Therefore, a real-time weight tuning strategy is proposed to solve time-varying multi-objective control problems, where the weight of each objective can be adjusted with respect to different operating conditions. In addition, simulation results demonstrate that the ACC system with the proposed real-time weighted MPC (RW-MPC) can provide better performance than that using constant weight MPC (CW-MPC) in terms of fuel economy and ride comfort. 相似文献
192.
EXPRESSION CLONING OF A PROTECTIVE LEISHMANIA ANTIGEN 总被引:5,自引:0,他引:5
郑时春 《西安交通大学学报(英文版)》1995,(2)
EXPRESSIONCLONINGOFAPROTECTIVELEISHMANIAANTIGENE.Mougneau,F.Altars,A.E.Wakil,ZhengShichun;T.Coppola,Z.Wang,R.Waldmann,R.M.Loc... 相似文献
193.
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
194.
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
195.
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
196.
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
197.
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
198.
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
199.
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
200.
In development projects there is only one problem, but it is huge: everything is connected to everything else. The authors
separated from the whole the following important issues: (1) Project management and coordination: The Recipient Country’s Aid Coordination Unit (ACU) and Project Implementation Unit (PIU) staffed with competent local experts
are necessary to hold the reform process memory. This issue is considered in the context of “Ownership” and “Government Leadership”
as it is recognized in donor aid forums in the last decade. (2) Human resource development: Most technical assistance is oriented toward providing solutions, and the development of local capacities is ignored. The
authors point out the importance of specially selected local experts—the “Technical Communication Officers”. (3) Institutional functioning: A ‘process consultation’ approach to institutional restructuring is promoted in which the Recipient has the key role. It
is also recommended that the Recipient is the initiator of technical assistance in the projects. (4) Design standards are a recurrent and difficult problem. Recommendations are necessary how to transit to the new standards and how to mediate
their approval process. (5) Procurement and management of consulting services: The authors argue that the recipient country qualified professionals have to be in the lead role. The vignettes in the paper
are from the “real world” although they are modified slightly to protect privacy. 相似文献