How EPC firms can enter the nuclear renaissance

the so called “nuclear renaissance” is creating a millionaire market for new nuclear reactors. Few firms have the capabilities to work in this complex and highly demanding market, whereas many other are investigating the option to enter. Quite surprising the international scientific literature provides information regarding the high-level governmental aspects of nuclear power programs in different countries while the analysis at firm level is almost inexistent. Moreover the usual business models for the manufacturing industry are not suitable since the nuclear market is very peculiar. In particular is unclear how an EPC (Engineering Procurement and Construction) company can enter in it. This paper deals with this question investigating how an EPC firms or general contractor can enter in the nuclear market. The case study methodology has been widely used to understand the time, cost, enabling factors and barriers to enter in the nuclear business in the most important roles: Architect/Engineering, NSSS supplier, TG supplier, Construction. The results show that there are strong similarities among companies acting as main contractor in the same field; therefore it is possible to generalize a large set of meaningful lessons learned

Fine-Structure Classification of Multiqubit Entanglement by Algebraic Geometry

We present a fine-structure entanglement classification under stochastic local operation and classical communication (SLOCC) for multiqubit pure states. To this end, we employ specific algebraic-geometry tools that are SLOCC invariants, secant varieties, to show that for $n$-qubit systems there are $\lceil\frac{2^{n}}{n+1}\rceil$ entanglement families. By using another invariant, $\ell$-multilinear ranks, each family can be further split into a finite number of subfamilies. Not only does this method facilitate the classification of multipartite entanglement, but it also turns out to be operationally meaningful as it quantifies entanglement as a resource.Comment: 11 pages, 2 figures, Minor changes, Published versio

b-Initio Molecular Dynamics Simulation of High Temperature GeO2

We made a series of molecular dynamic simulations to get a representative, high temperature GeO2 system to eventually be quenched down to room temperature so as to obtain an amorphous system to be studied under pressure for comparison to experimental results. We carefully generated an initial configuration such that all simulations have entirely been carried out by ab-initio methods in the range 10K-3000K

Improving Projects Performance With Lean Construction: State Of The Art, Applicability And Impacts

Construction projects are not often delivered on time and on budget and re-workings are usually required to satisfy customer’s needs. This papers aims to present an overview of Lean Construction (LC) and how this construction philosophy tackles the aforementioned problems. The research is empirical and based on data from the literature, 7 new Case Studies built with primary data, 12 Case Studies on CLIP (Construction Lean Improvement Programme) projects, 4 semi-structured Interviews with Firms adopting LC and several interviews (face to face and email) with LC experts. The results show as LC can achieve astonishing results focusing on reducing waste caused by unpredictable work-flow, paying attention on how every single activity affects the next one and avoiding reworking considered as no valued-added activity. The paper provides three original set of results: (1) a fuzzy cognitive map of LC showing how the different elements are linked to each other; (2) a pathway for the implementation of LC; (3) a synthesis of the strengths and the weaknesses of LC merging literature review with case studies analysis. In particular (3) shows the dimensions of projects adequate for lean construction, the increase of productivity and time reduction due to LC implementation and finally the reasons moving firms to adopt LC

Automotive diesel engine transient operation: modeling, optimization and control

Traditionally, the study of internal combustion engines operation has focused on the steady-state performance. However, the daily driving schedule of automotive engines is inherently related to unsteady conditions. There are various operating conditions experienced by (diesel) engines that can be classified as transient. Besides the variation of the engine operating point, in terms of engine speed and torque, also the warm up phase can be considered as a transient condition. Chapter 2 has to do with this thermal transient condition; more precisely the main issue is the performance of a Selective Catalytic Reduction (SCR) system during cold start and warm up phases of the engine. The proposal of the underlying work is to investigate and identify optimal exhaust line heating strategies, to provide a fast activation of the catalytic reactions on SCR. Chapters 3 and 4 focus the attention on the dynamic behavior of the engine, when considering typical driving conditions. The common approach to dynamic optimization involves the solution of a single optimal-control problem. However, this approach requires the availability of models that are valid throughout the whole engine operating range and actuator ranges. In addition, the result of the optimization is meaningful only if the model is very accurate. Chapter 3 proposes a methodology to circumvent those demanding requirements: an iteration between transient measurements to refine a purpose-built model and a dynamic optimization which is constrained to the model validity region. Moreover all numerical methods required to implement this procedure are presented. Chapter 4 proposes an approach to derive a transient feedforward control system in an automated way. It relies on optimal control theory to solve a dynamic optimization problem for fast transients. From the optimal solutions, the relevant information is extracted and stored in maps spanned by the engine speed and the torque gradient

A framework for the selection of the right nuclear power plant

Civil nuclear reactors are used for the production of electrical energy. In the nuclear industry vendors propose several nuclear reactor designs with a size from 35–45 MWe up to 1600–1700 MWe. The choice of the right design is a multidimensional problem since a utility has to include not only financial factors as levelised cost of electricity (LCOE) and internal rate of return (IRR), but also the so called “external factors” like the required spinning reserve, the impact on local industry and the social acceptability. Therefore it is necessary to balance advantages and disadvantages of each design during the entire life cycle of the plant, usually 40–60 years. In the scientific literature there are several techniques for solving this multidimensional problem. Unfortunately it does not seem possible to apply these methodologies as they are, since the problem is too complex and it is difficult to provide consistent and trustworthy expert judgments. This paper fills the gap, proposing a two-step framework to choosing the best nuclear reactor at the pre-feasibility study phase. The paper shows in detail how to use the methodology, comparing the choice of a small-medium reactor (SMR) with a large reactor (LR), characterised, according to the International Atomic Energy Agency (2006), by an electrical output respectively lower and higher than 700 MWe

Green Processing Route for Polylactic Acid–Cellulose Fiber Biocomposites

A completely green approach was adopted for the production of biocomposites of polylactic acid (PLA) and cellulosic fibers (CF) via functionalization of CF with an aqueous solution of poly(ethylene..

Variation in the stable isotope trophic position of the bluefish Pomatomus saltatrix (Linnaeus, 1766) from two Mediterranean sites: insights from a global meta-analysis

A direct consequence of sea warming is the shift in the distribution range of thermo-tolerant species that have the potential to determine novel inter-specific interactions, ultimately altering food web structures and ecosystem processes. In this study, we investigated the trophic position of the bluefish Pomatomus saltatrix (Linnaeus, 1766), a pelagic predator that has recently expanded its distribution in the Mediterranean basin and for which scant information is available on its functional role in recently-colonised areas. Nitrogen and carbon stable isotopes were determined in muscle tissues of bluefish specimens collected in south-east Italy in the Gulf of Taranto (NW Ionian Sea) and in the Strait of Otranto (SW Adriatic Sea) at two coastal sites showing contrasting oceanographic conditions. The bluefish trophic position (TP) was estimated using locally abundant forage fish species as isotopic baselines. The results indicated for bluefish from the Strait of Otranto a TP value of 5.1, significantly higher than that determined in the Gulf of Taranto (4.2), and exceeding stomach content-based estimations reported by the online database FishBase and by literature sources. A synthesis of 30 publications reporting isotopic data for the bluefish and its potential prey at a global scale indicated that the species’ trophic position varied considerably between 2.7 and 5.2. The observed variability depended on location and on the baseline species used in the estimations. Yet, a significant difference in trophic position was observed for bluefish from transitional and inshore environments as compared with offshore areas, mirroring the results obtained from the Gulf of Taranto and the Strait of Otranto. The findings of the study highlight the high trophic plasticity characterizing the bluefish in recently colonized areas, suggesting that it may play a key role in facilitating the expansion of its distribution range. However, additional investigations are essential to provide an advanced resolution of the bluefish functional role in Mediterranean coastal food webs

Looking back to see the future: building nuclear power plants in Europe

The so-called ‘nuclear renaissance’ in Europe is promulgated by the execution of two large engineering projects involving the construction of two European Pressurized Reactors (EPRs) in Flamanville, France and Olkiluoto in Finland. As both projects have faced budget overruns and delays, this paper analyses their governance and history to derive lessons useful for the construction of future projects. Analysis indicates that the reasons for these poor outcomes are: overoptimistic estimations, first-of-a-kind (FOAK) issues and undervaluation of regulation requirements. These pitfalls have the potential to impact on many other engineering construction projects and highlight fruitful areas of further research into project performance