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Material Research Related to Structural Pavement Failure on Motorway A32 in the Netherlands

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武汉理工大学学报 2010年第17期32卷 8-17页

作者： HOUBEN L J M MOLENAAR A A A ERKENS S M J G faculty Civil Engineering and Geosciences Delft University of Technology Ministry of Traffic Public Works and Water ManagementCentre for Transport and Navigation

In 2008 structural failures occurred on the asphalt pavement,with a hydraulic blast furnace slag base,of the motorway A32 (constructed in 1986～1988) in the Netherlands. Within a few weeks serious depressions occurred,in which the asphalt pavement was full of cracks and the base had a very low stiffness. In 2008 and 2009 the pavement including the base was rehabilitated over a length of 10 *** Dutch Ministry of Public Works has initiated an extensive research into the risks of occurrence of this type of unexpected structural damages on the main road network in the Netherlands. Among many other things this research includes material research into the base material of the A32 to find the cause of the structural *** total 130 cores,divided over 26 cross-sections,were drilled from the A32. The cross-sections were divided over 3 areas,with a high and low base stiffness respectively and also at heaves that had grown into the pavement since 1998. In areas with high base stiffness the cores mainly contained bound base material,in areas with low base stiffness mainly granular material and at the heaves it was a mix thereof. Standard (static) and dynamic crushing tests were done on the granular material. Dynamic and monotonic indirect tensile tests and compression tests were performed on the bound material. In all cases no systematic difference was found between the mechanical properties of the blast furnace slag base material from the heavily loaded right traffic lane and the material from the other *** is concluded that the pavement failure on the A32 is introduced by the occurrence of full depth asphalt fatigue cracks in the pavement that was originally designed for 12 years (but was never strengthened) in areas where the base stiffness always has been low or became low through crushing (that also has resulted in the heaves). Penetrated rainwater then has weakened the base and pumping has occurred,resulting into loss of bearing capacity and decrease of vo

关键词： structural failure blast furnace slags base laboratory testing

Target tracking method of Siamese networks based on the broad learning system

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 1043-1057页

作者： Dan Zhang C.L.Philip Chen Tieshan Li Yi Zuo Nguyen Quang Duy navigation College Dalian Maritime UniversityDalianChina Innovation and Entrepreneurship Education College Dalian Minzu UniversityDalianChina Computer Science and Engineering College South China University of TechnologyGuangzhouChina Department of Computer and Information Science Faculty of Science and TechnologyUniversity of MacaoMacaoChina School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina faculty of navigation Vietnam Maritime UniversityHaiphongVietnam

Target tracking has a wide range of applications in intelligent transportation,real‐time monitoring,human‐computer interaction and other ***,in the tracking process,the target is prone to deformation,occlusion,loss,scale variation,background clutter,illumination variation,etc.,which bring great challenges to realize accurate and real‐time *** based on Siamese networks promotes the application of deep learning in the field of target tracking,ensuring both accuracy and real‐time ***,due to its offline training,it is difficult to deal with the fast motion,serious occlusion,loss and deformation of the target during ***,it is very helpful to improve the performance of the Siamese networks by learning new features of the target quickly and updating the target position in time *** broad learning system(BLS)has a simple network structure,high learning efficiency,and strong feature learning *** at the problems of Siamese networks and the characteristics of BLS,a target tracking method based on BLS is *** method combines offline training with fast online learning of new features,which not only adopts the powerful feature representation ability of deep learning,but also skillfully uses the BLS for re‐learning and re‐*** broad re‐learning information is used for re‐detection when the target tracking appears serious occlusion and so on,so as to change the selection of the Siamese networks search area,solve the problem that the search range cannot meet the fast motion of the target,and improve the *** results show that the proposed method achieves good results on three challenging datasets and improves the performance of the basic algorithm in difficult scenarios.

关键词： broad learning system siamese network target tracking

Optic-electronics stereo system for spatial position measurement of railway track

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Optoelectronics Letters 2022年第7期18卷 434-439页

作者： Igor Konyakhin XIAO Han LI Renpu YANG Jiawen HUANG Guifu TAN Xin faculty of Engineering Research Applied Optic ITMO UniversitySaint Petersburg 197101Russia Chongqing Key Laboratory of Autonomous navigation and Microsystem Chongqing University of Post and TelecommunicationsChongqing 400065China

Railway departments in various countries are looking for a technology with convenient operation,low price,excellent measurement performance and stability for spatial position measurement of railway ***,we design an optic-electronics stereo system based on the principle of optical stereo *** experimental verification in the real railway environment shows that the performance of the system is that the longitudinal relative displacement measurement range is 200—10000 mm,the relative distance measurement range is 4500 mm and the measured root mean square(RMS)error value is less than 1.1 mm in the whole ***,it meets the relevant needs of the Russian Ministry of railways.

关键词： measurement. system price

Electronic warfare in the optical band:Main features,examples and selected measurement data

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Defence Technology（防务技术） 2021年第5期17卷 1636-1649页

作者： Roman Ostrowski Artur Cywinski Marek Strzelec Polish Naval Academy Navigation and Naval Weapons Faculty69Smidowicza Str.81-127GdyniaPoland Military University of Technology Institute of Optoelectronics2 Gen.S.Kaliskiego Str.00-908WarsawPoland

The paper presents the possibilities of,and methods for,acquiring,analysing and processing optical signals in order to recognise,identify and counteract threats on the contemporary *** main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated,including the acquisition of optical emitter signatures,as well as ultraviolet(UV)and thermal(IR)*** physical parameters and values describing the emission of laser radiation are discussed,including their importance in terms of creating optical ***,it has been shown that in the transformation of optical signals into signatures,only their spectral and temporal parameters can be *** was confirmed in experimental part of the paper,which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser *** has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in“solar-blind”band,various events can be identified quickly and *** same is true for IR signatures,where the amplitudes of the recorded signal for several wavelengths are *** was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground,namely Rocket Propelled Grenade(RPG)launches and explosions after hitting targets,trinitrotoluene(TNT)explosions,firing armour-piercing,fin-stabilised,discarding sabots(APFSDS)or high explosive(HE)*** final section describes a proposed model database of emitters,created as a result of analysing and transforming the recorded signals into optical signatures.

关键词： Optoelectronics Electronic warfare Optical signature

Multicriteria Decisions for Vessels Routing

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Multicriteria Decisions for Vessels Routing

The Model Research on the Flooding Time of the Warship Damaged Compartment

作者： Wlodzimierz Filipowicz faculty of navigation Gdynia Maritime University

＜正＞Traffic separation schemes along with Vessel Traffic Services （VTS） have significantly improved the existing safety standards within restricted areas. The VTS is any service designed to improve safety and efficiency of traffic and protection of the environment. It may range from the provision of simple information messages to extensive management of traffic within a port or *** its aim is clearly defined one can put a question of possible development. Primarily traffic services are to be more active and scientific background of its activity should be more deeply explored. Passage recommendation and selection of routes are within a scope of interest of each traffic operator. It is assumed that computerized decision support tools will be widely used. This paper is devoted to upgrading hierarchy among available options whenever decisions regarding route selection or routes assignment are considered. Multi-objective approach is presented in context of choosing the best passage for a single vessel. An idea of traffic control within restricted waters is also included. Decision-making as a process is briefly discussed.

关键词： multicriteria decisions routes selection traffic control multicriteria optimisation

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Journal of Shipping and Ocean Engineering 2012年第4期2卷 217-223页

作者： Waldemar Mironiuk faculty of navigation and Naval Weapons Naval Academy Gdynia 81-103 Poland

Research on damage stability and unsinkability is a valuable source of knowledge of behaving a ship while flooding its compartments. The time when compartment is flooded （ty） and stability parameters are key elements which have influence on a rescue action. The knowledge of the time mentioned is very important for a commanding officer to make decisions while fighting for survival of the ship. Therefore, the purpose of research was to develop a method to accurately and quickly calculate the flooding time of selected ship compartment. To provide the information about the time ty, a new method was designed. This method was based on an accurate determination of the amount of water entering to the compartment. For this purpose, the permeability depends on the water level in the compartment. Next, the computer program was built for both the time tfcalculation and showing the flooding process. This method was tested experimentally and the results of the tests are presented in the paper. In the next part of research, which was carried out on the laboratory stand bed, the flooding time of damaged compartment of warship model was measured. The results of calculation are compared to the experiments and discussed.

关键词： Ship stability flooding time warship.

Design and realization of synchronization circuit for GPS software receiver based on FPGA

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Journal of Systems Engineering and Electronics 2010年第1期21卷 20-26页

作者： Xiaolei Yu Yongrong Sun Jianye Liu Jianfeng Miao navigation Research Center Nanjing University of Aeronautics and Astronautics Nanjing 210016 E R. China faculty of Science and Technology Deakin University Geelong VIC 3217 Australia Department of Land Surveying & Geo-Informatics Hong Kong Polytechnic University Hong Kong E R. China

With research on the carrier phase synchronization and symbol synchronization algorithm of demodulation module, a synchronization circuit system is designed for GPS software receiver based on field programmable gate array （FPGA）, and a series of experiment is done on the hardware platform. The result shows the all-digital synchronization and demodulation of GPS intermediate frequency （IF） signal can be realized and applied in embedded real-time GPS software receiver system. It is verified that the decision-directed joint tracking algorithm of carrier phase and symbol timing for received signals from GPS is reasonable. In addition, the loop works steadily and can be used for receiving GPS signals using synchronous demodulation. The synchronization circuit for GPS software receiver designed based on FPGA has the features of low cost, miniaturization, low power and real-time. Surely, it will become one of the development directions for GPS and even GNSS embedded real-time software receiver.

关键词： software receiver synchronization circuit field programmable gate army GPS joint tracking algorithm.

Formation control with obstacle avoidance of second-order multi-agent systems under directed communication topology

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Science China(Information Sciences) 2019年第9期62卷 144-157页

作者： Guoxing WEN C.L.Philip CHEN Hui DOU Hongli YANG Chunfang LIU College of Science Binzhou University Department of Computer and Information Science Faculty of Science and Technology University of Macau College of navigation Dalian Maritime University State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences Mathematics and Systems Science College Shandong University of Science and Technology

This paper addresses the obstacle avoidance problem of formation control for the multi-agent systems modeled by double integrator dynamics under a directed interconnection topology. The control task is finished by a leader-follower formation scheme combined with an artificial potential field(APF) *** leader-follower scheme is carried out by taking the desired trajectory with the desired velocity as virtual leader, while the APF method is carried out by dealing with the obstacles as the high potential points. When the obstacle avoidance tasks are finished, the artificial potential forces degrade the formation performance, so their undesired effects are treated as disturbances, which is analyzed by the robust H∞performance. Based on Lyapunov stability theory, it is proved that the proposed formation approach can realize the control objective. The result is also extended to the switching multi-agent formation. The effectiveness of the proposed formation scheme is further confirmed by simulation studies.

关键词： formation control obstacle avoidance artificial potential field method H_∞ performance second-order multi-agent system directed topology

Blended Learning Will Be Applicable in Maritime Education and Training

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Journal of Shipping and Ocean Engineering 2016年第1期6卷 31-34页

作者： Yu Haiyan Department of navigation Faculty of Merchant Marine College Shanghai Maritime University Shanghai CHINA

With the revision work of the IMO Model Course 6.09, the trainee-centered methodology is greatly highlighted, together with the newly merging technology for education, especially for language learning. This paper will consider blended learning, for instance. Blended learning is adorable for many educators in recent years, which demonstrates the principle of student-centered as well as alternates the role of the teachers from the traditional way. MOOC （Massive Online Open Course） is initiated in most schools as well, for the purpose of mutual share of the best education in the world. Within the framework of blended learning, the MOOC can also be the essential section in a whole circle. With some successful examples for the application of blended learning in elementary and middle schools, the author is suddenly inspired to make assumptions for better MET （maritime education and training）： the blended learning is applicable in MET to stimulate the students＇ initiatives.

关键词： Blended learning MOOC MET.