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Interferometry by multidimensional deconvolution applied to Controlled-Source Electromagnetic data replaces the medium above the receivers by a homogeneous halfspace, suppresses the direct field and redatums the source positions to the receiver locations. In that sense, the airwave and any other interactions of the signal with the air-water interface and the water layer are suppressed and the source uncertainty is reduced. Interferometry requires grid data and cannot be applied to line data unless the source is infinitely long in the crossline direction. To create such a source, a set of source lines is required. We use an iterative algorithm to determine the optimal locations of these source lines and show that more source lines are required if the source is towed closer to the sea bottom and closer to the receivers.

This summary provides a brief account of the background, approach, analysis and conclusions of this thesis. Construction is characterized as a high hazard industry which contains a wide range of activities including construction, alteration and/or repair (Michaels, 2010). The organizations involved in construction projects are project owner, designer, contractor/sub-contractors, suppliers. According to Benton&McHenry (2010), the material-delivery system is an important success factor for a construction project, which involves many companies such as professionals and suppliers. However, suppliers, which have limited control on a construction project, are an important organization involved in a material-delivery system of construction projects. Thus improvements on the performance of suppliers can contribute to an effective and efficient material-delivery system of a construction project. In a construction project, last-minute deliveries are one of the problems suppliers have encountered. Therefore, this research is based on the notion that reducing the influences exerted by last-minute deliveries on construction supply chain can improve suppliers’ performance, which in turn contributes to an effective and efficient material-delivery system of a construction project. It aims to explore how the construction supply chain should be in order to have less last-minute deliveries. The main research questions stem from these ideas and are defined as follows: How can the planning process be organized for suppliers from a supply chain perspective in order to lead to a better process with less last minute deliveries to construction sites? To answer this main research question, first a literature review is conducted to explore what is already known about how to improve the performance of material-delivery system of construction projects. Prior work on the improvement of material-delivery system was found to address some issues on two aspects: 1) Construction project management Increase the material-delivery system of construction projects from a project management perspective 2) Construction supply chain Increase the material-delivery system of construction projects from a supply chain perspective But improving the performance of construction supply chain from a supplier’s perspective by reducing the number of last-minute deliveries is not explored. To answer the main research questions, seven research sub-questions are formulated. The process of answering the sub questions are divided into two phases: analysis phase and design phase. The analysis phase is focusing on clarifying the current problem situation and the reasons for higher number of last-minute deliveries to construction sites. While the design phase aims to identifying best practices concerning construction supply chain and applying these practices to the supply chain of one construction projects supplier --- Legrand B.V.. The seven research sub-questions are listed below: Analysis Phase 1) What is the current situation related to the construction organization, supply chain process and the problem of last minute-deliveries 2) What is the current situation related to the planning process for construction supply chain? 3) What are the reasons for a higher number of last-minute deliveries in construction projects? Design Phase 4) What are the best practices concerning the planning process in construction projects from a supply chain perspective so far? 5) What can be learned by evaluating the best practices in the current situation in order to make recommendations on how the redesigned planning process should be? 6) What is the recommendation on how the planning process can be organized in construction projects from a supply chain perspective? 7) What are the benefits of the recommended solutions for both Legrand and related stakeholders? In this thesis, a multi-method strategy including interview, document review and literature review is used for data collection in order to increase the credibility and validity of the results (K.Yin, 2003). Additionally, root-cause analysis is also used to find the root cause of higher number of last-minute deliveries to construction sites. The first two research sub-questions are about identifying the current situations with respect to construction organization structure, construction supply chain, problem scale of last minute deliveries and the current planning process in construction projects from a supply chain perspective, thus related data are needed to collect to visualize these current situations. In this research, literature review and document review are conducted to identify the current situations. Additionally, eight interviews in related construction organizations also contribute to the identification of the current situations. Thus, the credibility and validity of the current situation are increased by employing these three kinds of data collection methods. In chapter 4 which is for answering research sub-question 3, root-cause analysis is used to identify the root causes for higher number of last-minute deliveries to construction sites. Root cause is the most basic reason for an undesirable condition or problem which, if eliminated or decreased, would have prevented or mitigated it from occurring (Paulf, Dell, & Anderson, 1993). In this research, one of the technic for root cause analysis ----- events and causal factors analysis is chosen as a tool for analyzing, because the construction organization is complex and also there are surrounding conditions (Paulf, Dell, & Anderson, 1993). For research sub-question 4 which is focusing on finding the best practices concerning the planning process in the construction projects from a supply chain perspective, literature review is considered as a method. According to Yin (2003), one approach which can be considered as an analytic strategy is to use analytic technique such as creating some requirements and showing if some evidence satisfies those requirements. Thus in this research, sub question 5 and 6 are answered by displaying all the alternative solutions identified in Chapter 4 and evaluating them in the current situation by means of balanced scorecard. According to the interviews and related document, literatures, it derives that there are three controllable root causes for the higher number of last-minute deliveries to construction sites:  Viable demand from client  Imperfect design  Lack of communication among construction contractors In order to reduce the number of last-minute deliveries to construction sites caused by the three controllable root causes, five recommendations have been made for the suppliers involved in construction projects. The five recommendations have different priorities. The most promising strategies are Partnership development, and building information modeling. Firstly, by participating into the design phase of a construction project and simulating the whole construction process, not only the number of rush orders caused by imperfect design and lack of communication among the whole construction organization can be reduced, but also this strategy can benefit the whole construction organizations. On the other hand, agile supply chain, logistics centers are also two strategies which can improve supplier’s construction supply chain performance by quickly responding customers’ needs, therefore mitigating the influences exerted by rush orders. Thirdly, postponement by means of modularization, standardization is also a promising strategy, although most of the electrical materials for construction projects are already standardized. It indicates that the standardization can be improved to a more detailed level, which makes the assembly on sites more flexible, so urgent demands from customers can be satisfied more quickly. This thesis contributes to both theory and management in the following ways: With respect to the academic contribution of this research, it can be found on the integration of expertise and research efforts aiming to result in the advancement of knowledge on the field of construction supply chain management and logistics. It may resolve theoretical questions such as whether the number of last-minute deliveries in construction projects can be reduced by redesign the construction supply chain. Bridging this scientific gap can lead in substantial conclusions and valuable practical applications. In addition, the managerial contribution of this research can be seen on the number of managerial terms intervening in this endeavor. Since several years ago, most of the manufacturing companies recognized that supply chain management can be a new way of doing business. The implementation of this new approach was a consequence of various changes in manufacturing environments. All these indicate that construction logistics is an interesting area for construction suppliers to make higher profit. Also, for construction project managers, construction logistics can help them understand the projects and the planning procedure better.

Controlled‐source electromagnetics (CSEM) has been used as a de‐risking tool in the hydrocarbon exploration industry. Although there have been successful applications of CSEM, this technique is still not widely used in the industry because the limited types of hydrocarbon reservoirs CSEM can detect. In this paper, we apply the concept of synthetic aperture to CSEM data. Synthetic aperture allows us to design sources with specific radiation patterns for different purposes. The ability to detect reservoirs is dramatically increased after forming an appropriate synthetic aperture antenna. Consequently, the types of hydrocarbon reservoirs that CSEM can detect are significantly extended. Because synthetic apertures are constructed as a data processing step, there is no additional cost for the CSEM acquisition. Synthetic aperture has potential for simplifying and reducing the cost of CSEM acquisition. We show a data example that illustrates the increased sensitivity obtained by applying synthetic aperture CSEM source.

Controlled-source electromagnetics (CSEM) has been used as a derisking tool in the hydrocarbon exploration industry. We apply the concept of synthetic aperture to the lowfrequency electromagnetic field in CSEM. Synthetic aperture sources have been used in radar imaging for many years. Using the synthetic aperture concept, big synthetic sources can be constructed by adding the response to small sources (building blocks) in different ways, and consequently, big sources with different radiation patterns can be created. We show that the detectability of hydrocarbons is significantly enhanced by applying synthetic aperture to CSEM data. More challenging targets such as deep reservoirs (4km belowsea floor) can be detected. The synthetic aperture technique also increases the sensitivity of the field to subsurface targets in the towing streamer acquisition.We also show that a pseudovertical source (orthogonally distributed dipole pairs) can be constructed synthetically, and that the detection capability of this pseudovertical source is increased by applying field steering. The synthetic aperture concept opens a new line of research in CSEM, with the freedom to design suitable synthetic aperture sources for a given purpose.

With interferometry applied to controlled-source electromagnetic data, the direct field and the airwave and all other effects related to the air-water interface can be suppressed in a data-driven way. Interferometry allows for retreival of the scattered field Green’s function of the subsurface or, in other words, the subsurface reflection response. This reflection response can then be further used to invert for the subsurface conductivity distribution. To perform interferometry in 3D, measurements on an areal grid are necessary. We discuss 3D interferometry by multidimensional deconvolution in the frequency-wavenumber and in the frequency-space domains and provide examples for a layered earth model. We use the synthetic aperture source concept to damp the signal at high wavenumbers to allow large receiver sampling distances. Interferometry indeed increases the detectability of a subsurface reservoir. Finally, we discuss the dependency of the accuracy of the retrieved reflection response on the two crucial parameters: the conductivity of the seabed at the receiver location and the stabilization parameter of the least-squares inversion.