• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 631
  • 192
  • 129
  • 44
  • 34
  • 29
  • 25
  • 17
  • 13
  • 6
  • 6
  • 6
  • 5
  • 5
  • 4
  • Tagged with
  • 1271
  • 378
  • 365
  • 342
  • 111
  • 89
  • 80
  • 77
  • 62
  • 60
  • 60
  • 56
  • 55
  • 55
  • 55
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Contribution à la conception et la réalisation de microscopes champ proche en bandes de fréquences microondes et millimétriques : application à l’évaluation non destructive / Contribution to the conception and the realization of near-field microscopes in microwave and millimeter-wave frequency bands : application to non destructive testing

Wang, Mingming 30 June 2010 (has links)
Les techniques de microscopies hyperfréquences à balayage en champ proche connaissent un intérêt grandissant. Ces méthodes offrent des possibilités de caractérisations surfaciques et sub-surfaciques de matériaux par une mesure sans contact, non invasive et non destructive. Elles permettent également de lever les restrictions concernant la résolution spatiale limitée des méthodes classiques de caractérisation hyperfréquence. Néanmoins, l’instrumentation qui est associée usuellement à ce type de caractérisation, généralement un analyseur de réseaux conventionnel, s’avère surdimensionné pour des applications hors laboratoire. Dans ce travail de thèse, nous proposons une instrumentation complète combinant les techniques multi-port et les techniques de microscopie champ proche. Les étapes de conception et de réalisation de systèmes multi-port opérant en gammes de fréquences micro-ondes et millimétriques sont décrites. Les travaux menés s’inscrivent dans la volonté de proposer des instruments intégrant les ressources matérielles et logicielles. Les potentialités de ces systèmes sont illustrées au travers de la mise en œuvre de bancs automatisés permettant d’effectuer des mesures du coefficient de réflexion en une ou deux dimensions. La démonstration de l’apport de la technique multi-port est faite au travers d’exemples traitant du cas de défauts de nature métallique ou diélectrique, débouchant ou non débouchant en surface d’un échantillon. Ces dispositifs ont pour ambition de sortir des laboratoires de recherche afin d’adresser des applications dans le domaine de l’Evaluation Non Destructive (END). / Scanning near-field microwave microscopy (SNMM) techniques have become important tools in the imaging of materials. These methods offer the possibility of characterizing surface and subsurface materials in a non-contact, non-invasive, and non-destructive way. In comparison with conventional microwave characterization techniques, the spatial resolution has been improved in a large extent with the development of the SNMM. Nevertheless, these techniques generally require the use of an automatic network analyzer that is oversized for applications outside the laboratory. In this work, we propose a new instrumentation that combines the multi-port technique and microscopy techniques. The design and realization of multi-port systems in the microwave and millimeter-wave frequency bands are described. The investigations are driven by the will to propose instruments integrating the hardware and software resources. The potentialities of the systems proposed are illustrated trough applications in the Non Destructive Testing field in both microwave and millimeter-wave frequency bands. The validity of the approach proposed is applied for 1-D and 2-D crack detection. It is demonstrated that these systems present a viable and promising alternative to the costly heterodyne principles.
12

On Optimizing PSA Berth Planning System

Teo, Chung Piaw, Dai, Jim, Moorthy, Rajeeva Lochana 01 1900 (has links)
Competition among container ports continues to increase as the differentiation of hub ports and feeder ports progresses. Managers in many container terminals are trying to attract carriers by automating handling equipment, providing and speeding up various services, and furnishing the most current information on the flow of containers. At the same time, however, they are trying to reduce costs by utilizing resources efficiently, including human resources, berths, container yards, quay cranes, and various yard equipment. When planning berth usage, the berthing time and the exact position of each vessel at the wharf, as well as various quay side resources are usually determined in the process. Several variables must be considered, including the length overall (LOA) and arrival time of each vessel, the number of containers for discharging and loading, and the storage location of outbound/inbound containers to be loaded onto/discharged from the corresponding vessel. Furthermore, we aim to propose berthing plan that will be "robust", since the actual arrival time of each vessel can vary substantially from forecast. This is particular important for vessels from priority customers (called priority vessels hereon), who have been promised berth-on-arrival (i.e. within two hours of arriving) service guarantee in their contract with PSA. A robust plan will also helps to minimize the frequent updates (changes) to berthing plan that have repercussion in resource and sta deployment within the terminal. Thus, the problem reduces to one of finding a berthing plan, so that priority vessels can be berthed-on-arrival with high probability, and the vessels can be berthed as close to their preferred locations as possible, to reduce the cost of transporting the containers within the terminal. In this paper, we described an approach to address this problem. / Singapore-MIT Alliance (SMA)
13

An Analysis for The Present Development and The Strategical Improvement of Taiwan Free Trade Zone

Chang, Tien-ming 31 July 2006 (has links)
Abstract Because of the trend of globalization and liberalization, every enterprise has actively developed the operation model for their global expansion in order to raise their competitive advantage. In the supply chains of international enterprises, there are a lot of serious competitions which are not just between company and company, but between country and country as well. Every country in the world has legislated the special law which is to give some special areas and eliminate the obstructers which would hold back activities of multinational from internal enterprises in order to satisfy with the demands from all multinationals in the world. Currently, there are about two thousands to five thousands free trade zones or the trade zones that are similar to free trade zones in the world, and they have turned into a very important circulation core and transaction core for international trade. On July 23, 2003 Taiwan was published the operation statute and the operation order of free trade zone by our president. After that, its related accessory schemes have established continually, and amply expanded their utilities. Because of that, this situation has helped free trade zone to have successfully performed its strength and to have assisted to break the predicament of industry development. Currently, In Taiwan, although it has five free trade zones that are Kaohsiung Port, Keelung Port, Taipei Port, Taichung Port and Taoyuan Airport Cargo Terminal, are stationed by eighteen manufacturers, the result of the operation has not reached our expectation. However, this research would be focused on the manufacturers¡¦ satisfaction with the recent standard of free trade zone. The result of this research which is gotten by information collection and data analysis shows the recent statutes and regulations of free trade zone should be revised the following issues: 1. Cancel the regulation of 5% aborigine employment limitation. 2. Simplify the transiting customs formalities and autonomous management methods. 3. Abolish employment regulation of the foreign labors` salary which must to conform to the basic salary regulation. 4. Loosen restrictions on business scope in free trade zone for mainlander. However, there is a suggestion which is our government would need to revise the related statutes and the regulations as quickly as possible in order to operate free trade zone successfully! . Key words: free trade zone, Kaohsiung Port, Keelung Port, Taipei Port, Taoyuan Airport Cargo Terminal and Taichung Port
14

The Impact of Kaohsiung Port Privatization on Union Reconstruction under the Globalization

Yu, Po-lo 11 September 2006 (has links)
none
15

Extracting MOSFET Small Signal Equivalent Circuit and Substrate Parameters with Four Port De-embedding Method

Chen, Chun-chung 02 September 2009 (has links)
Characteristics of small signal components for circuit designers are very important in circuit design. Many researchers have been working hard on removing the unwanted parasitic effects which is used to get the intrinsic characteristics of the small signal parameters. In this thesis, we propose a novel four-port de-embedding procedure which based on two-port cascade structure de-embedding procedure and combined with metal and polysilicon ground-shielded technology, and let four terminals of MOSFET are connected individually to four signal pads. With such de-embedding procedure, the intrinsic and substrate element values of small-signal model are extracted by different bias.
16

European deep-sea container terminals : locational and operational perspectives

Tabernacle, James Bernard January 1991 (has links)
No description available.
17

The development of the North-East coal ports 1815-1914 : the contribution of engineering

Rennison, Robert William January 1987 (has links)
The development of the ports of the North-East was a direct consequence of the region's increasing coal production; existing ports were expanded and new facilities created. Improvement required capital and it became necessary to form commissions to administer the ports, subsuming the powers of individuals and companies. Through them the greatest and most beneficial developments took place. Of an engineering nature, improvements involved rail transport, trans-shipment facilities, the building of docks and breakwaters, and river deepening and straightening. The advice of the nation's most eminent engineers was acted upon and, through the works undertaken, coal shipments f rom the North-East increased from 3 to 35 million tons per annum over the century which began in 1815. Certain ports were over-capitalised, others starved of funds, but by 1914 all competed on equal terms. Based on throughput, all exhibited similar capital expenditure and annual revenue. Development was not uniform but, generally, capital expenditure resulted in increased coal throughput and revenue. Docks were built as necessary, their costs comparable with those of other U. K. ports. Their value was marginal although two of them were so efficient that they were equalled in unit throughput only by Cardiff, the principal port of the analagous South Wales coalfield. Mining, railways and ports were inter-dependent, collieries owning staiths and several railways themselves operating docks. In 1865 the ports came to experience the virtual territorial monopoly of the North Eastern Railway, its financial power unrivalled. Itself operating docks, it came to determine the strategy of coal shipments. This thesis explores the evolution of the ports and their railways, the contribution made by the engineering profession to the development of both, the formation of the region's port authorities and the relationships which existed within and without the governing bodies.
18

A Study For The Development Of Seismic Design Specifications For Coastal Structures

Gozpinar, Erdem 01 January 2003 (has links) (PDF)
An evolving design philosophy for port structures in many seismically active regions reflects the observations that: -The deformations in ground and foundation soils and the corresponding structural deformation and stress states are key design parameters. -Conventional limit equilibrium-based methods are not well suited to evaluating these parameters. -Some residual deformation may be acceptable. Performance-based design is an emerging methodology whose goal is to overcome the limitations present in conventional seismic design. Conventional building code seismic design is based on providing capacity to resist a design seismic force, but it does not provide information on the performance of structure when the limit of the force-balance is exceeded. If we demand that limit equilibrium not be exceeded for the relatively high intensity ground motions associated with a rare seismic event, the construction cost will most likely be too high. If forcebalance design is based on amore frequent seismic event, then it is difficult to estimate the seismic performance of the structure when subjected to ground motions that are greater than those used in design. In this thesis a case study will be carried out on a typical port structure to show the performance evolution aspects and its comparison with damage criteria and performance grade in performance-based methodology.
19

Essai sur la morale de Port-Royal

Thomas, Jacques Franc̜ois. January 1942 (has links)
Thesis (doctoral)--Université de Paris, 1942. / "Liste des ouvrages port-royalistes consultés": p. [179]-182. "Liste des livres cites": p. [183]-185.
20

Development of a dynamic model for strategic port planning and investment

Audo, S. January 1985 (has links)
Different levels of congesti'on are 'encountered in ports all over the world and particularly in developing countries. Depending on the volume of traffic flow over time, the changes of development in the economy and industrial activity and the random arrival and service pattern of ships; the optimum berthing capacity resulting in minimum cost at any future time period has to be determined to avoid undesirable repercussions. The existing methods fail to provide the links between the aggregate economy, demand and optimal berthing capacity for all time periods of the planning horizon, and conventional techniques based on static frameworks are used to arrive at optimal strategies for specific times into the future. This study is an attempt to remedy those difficulties and relate future demand to optimal berthing capacity in an interactive dynamic fashion. Three models are developed: a forecasting model linking seaborne trade to gross domestic product, population, productions consumption and elasticity of demand;, a simulation model relating the various demand levels to different port configurations; and an investment model relating the resulting congestion cost to capital cost, where an optimal strategy in berthing capacity is achieved for the years 19859 19909 1995 and 2000. The last model has been extended using the above mentioned points in time to result in an optimal berthing capacity for any future time period within the planning horizon 1985 - 2000. This model is validated through forecasting, simulating and appraising the 1992 and 1998 results and reducing the amount, costs and time of work by 75 per cent.

Page generated in 0.0267 seconds