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The Challenge of Nuclear Reactor Structural Materials for Generation IV Nuclear Energy Systems

The Challenge of Nuclear Reactor Structural Materials for Generation IV Nuclear Energy Systems

Nuclear power technology can be ranked in stages, or generation. Generation IV systems project in-service and off-normal levels that are beyond current nuclear industry experience, as well as most previous experience with developmental systems. All of them require relatively long service lifetimes for materials and relatively high burn-up for fuels. Therefore, such essential activities as candidate selection, fabrication development, properties assessment and qualification, irradiation testing & safety demonstration might be taken into action together with system establishment of new codes, standards and regulations.

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Cross-Cutting Ideas for a Fusion DEMO Plant with Current and Generation IV Nuclear Power Plants

Cross-Cutting Ideas for a Fusion DEMO Plant with Current and Generation IV Nuclear Power Plants

The fusion DEMO program of Korea has been conceptualized to realize magnetic fusion energy with the tokamak concept at the end of 2030 s or early 2040 s. In this program, to expedite the development of a fusion DEMO plant, cross-cutting based on the commonalities between the fusion DEMO plant and existing systems. Among the existing systems, the current and generation IV nuclear power plants will have many areas of com- monalities with the fusion DEMO plant including regulatory requirements and licensing processes, codes and standards, design methods and computational codes for thermo hydraulic analysis, and safety analysis methods. Theses commonalities will be used for discovering a pathway of resolving the nested logic dilemma incurred by the inherent first-of-a-kind nature of the fusion DEMO plant. This paper presents the result of an exploratory study on the subject cross-cutting.

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Efficient Uncertainty Quantification for a Fast-Spectrum Generation IV Reactor System

Efficient Uncertainty Quantification for a Fast-Spectrum Generation IV Reactor System

operation. Core simulators enable designers to model reactor operation, performance, and safety before the expensive construction of the plant takes place. Quantification and understanding of simulators’ uncertainties also allow designers the freedom to change design to reduce design margins which greatly affect operational cost and profit. In addition, with the introduction of advanced reactor systems, i.e. Generation IV reactor systems, the accuracy of the simulation tools needs to be assessed in regard to key core attributes such as decay heat, peak fast fluence, discharge burnup, coolant void worth, etc since the experience with light water reactors (LWR) will not provide an informed basis for assessment due to the large difference in irradiation environment. It is the purpose of this study to use the method of uncertainty quantification to calculate uncertainties found in key core attributes for an advanced reactor system due to cross-sections uncertainties. 1.3 Uncertainty Quantification

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Numerical Investigation of Flow in Generation IV Pebble Bed Gas Cooled Core Reactors

Numerical Investigation of Flow in Generation IV Pebble Bed Gas Cooled Core Reactors

A Very High Temperature Gas-cooled Reactor (VHTR) is one of the renewed reactor designs to play a role in nuclear power generation. The Generation IV International Forum findings relative to the future nuclear systems (sustainability, security and reliability, economy, non-proliferation and physical protection) have given new impetus to graphite-moderated VHTRs. These reactors design concept is currently under consideration and development worldwide. The high modular VHTR concept exhibits inherent safety features due to the low power density and the large amount of graphite present in the core, which gives a large thermal inertia in the event of accidents as loss of coolant. These passive concepts were first introduced in German HTR-Module (pebble fuel) design [1, 2]. The fuel design of fissile kernels coated with carbon and silicon carbide layers mixed with graphite is suitable for reaching very high burn up and ensures a full confinement of volatile fission products during normal and abnormal

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From NDE to Prognostics: A Revolution in Asset Management for  Generation IV Nuclear Power Plants

From NDE to Prognostics: A Revolution in Asset Management for Generation IV Nuclear Power Plants

The adoption of advanced diagnostic and prognostic technologies for Generation IV nuclear power plants can significantly impact plant economics. However, before the deployment of such systems is possible it is necessary to demonstrate methodologies, understand stressors, sensors, communication, analysis and quantify uncertainty in remaining life prediction as well as to demonstrate long term monitoring system reliability. But in order for these approaches to be successful it will require the engagement of researchers, Gen IV designers, component manufacturers, codes and standards personnel, material suppliers, and regulators working as a team to develop, demonstrate and validate these new and advanced measurement and monitoring technologies for Gen IV NPPs. The engagement of these many diverse experts must occur NOW in order for these advances to be realized. Otherwise, Gen IV plants will simply be extensions of the design, operating and performance standards of the current fleet of light water reactors.

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Generation IV Material issues - Case SCWR

Generation IV Material issues - Case SCWR

Generation IV nuclear power concepts have become an active research topic all over the world during the last 5 - 10 years. There are six concepts accepted by the GenIV international forum (GIF) with the common aims to promote both efficiency and safety of the technology. New concepts will offer attractive features but at the same time they also bring new and demanding challenges e.g. for the materials technology due to increased operating temperatures and irradiation doses as well as more aggressive coolants and/or longer life time expectations than of GenII and GenIII plants. In this paper an overview of the material issues is given with special emphasis on one of the 6 concepts namely the supercritical light water reactor concept (SCWR).

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THREE INVESTMENT SCENARIOS FOR  FUTURE NUCLEAR REACTORS IN EUROPE

THREE INVESTMENT SCENARIOS FOR FUTURE NUCLEAR REACTORS IN EUROPE

In a context of post-Fukushima nuclear development and climate protection, this article addresses the issue of investment in future nuclear technologies in Europe, focusing in particular on Generation IV nuclear reactors or fast reactors (FR). The MIT publication called The future of nuclear power after Fukushima (Joskow and Parsons 2012) reports the expected growth of nuclear power in the world fleet (1% per year through 2035 in OECD countries and 6% per year in non-OECD countries through 2035). This report states that nuclear growth will not be significantly reduced, except in Germany, Japan and Switzerland, thus an increase in the consumption of natural uranium can still be expected. This nuclear growth and carbon reduction measures such as those detailed in the European Climate Action and Renewable Energy Package (Da Costa et al. 2009) could make FRs a viable choice for further electricity

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Exploiting Reverse Correlation for the Generation of Virtual Characters from Personality Traits

Exploiting Reverse Correlation for the Generation of Virtual Characters from Personality Traits

A genetic algorithm converges to a good solution when at each evolution step the average fitness value of the new generation increases. The convergence of the algorithm is not guaranteed; it depends on the choice of a proper fitness function together with the choice of the election, mutation, and cross-over percentages. These latter values are normally determined by a human operator through trial and errors. The computation of new generations ends when one of the following two conditions are fulfilled: first, the fitness value of one of the individuals reaches a satisfying value, which means that a good approximate solution is found; second, the maximum computation time elapses. In this traditional approach of genetic computation, the user evaluates the best solution of the latest generation and accepts it. If the solution is not satisfactory, the user fine tunes the election, mutation, and cross-over percentages, and re-runs the evolution aiming at better results. However, for some problems a fitness function cannot be identified because it is related to tasks that only humans can accomplish (such as evaluating the quality of a picture). This has led to the introduction of Interactive Genetic Algorithms (IGAs): in this approach genetic algorithms are run by asking humans to perform an evaluation for each individual of a generation. The evaluation is directly used as fitness value or is used to calculate it.

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A Review Of Synthetic Data Generation Methods For Privacy Preserving Data Publishing

A Review Of Synthetic Data Generation Methods For Privacy Preserving Data Publishing

part of the data. It might be less number of attributes than the original data contains or constrained on the value of one or more attributes. User shall be allowed to personalize the generation of data, of course with preservation of privacy. The synthetic data generator preserves privacy pertaining to the list of attributes or constraints the user has specified. This will increase the utility of the generated data since information loss due to privacy preservation is less compared to the information loss that have occurred to privacy preservation of complete original data. As some algorithms support specification of size of the data generated, the data model shall provide simple method to scale up or scale down the size of the data generated. Gibbs, random and other sampling techniques are being used to sample the data from the model; it shall be improved to represent the original data as accurately as possible without compromising on the privacy.

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Coefficient of Engine Flexibility as a Basis for the Assessment of Vehicle Tractive Performance

Coefficient of Engine Flexibility as a Basis for the Assessment of Vehicle Tractive Performance

The paper attempts to analyze full load characteristics of over 500 combustion engines. Using statistical tools, the author determined the value of the coefficient of flexibility. Engine flexibility is the capability of the engine to adapt to varying loads. Importantly, in the investigations, the author took into account the parameters calculated in the course of the investigations on a chassis dynamometer, i.e., actual, not taken from technical specifications of brand new vehi‑ cles. Different stages of operating wear allow a better characterization of the population. Subsequent utilization of the results in tractive calculations is more reliable. The engines were divided into in six groups, depending on the type of fuel system: fuel injected gasoline and turbocharged gasoline, spark ignition LPG, naturally aspirated diesel and turbo‑ charged diesel. However, engines running on alternative fuels are characterized with a greater flexibility than the fuel injected base engines. Conformity of flexibility of fuel injected and LPG IV generation engines have been observed, which confirms the appropriateness of engine adaptation to alternative fueling. Gasoline engine supercharging allowed a reduction of the maximum engine speed of the maximum torque, which extends the range of analyzable speeds for flexibility and consequently, the flexibility as such.

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Synthesis of Planar Mechanisms; Part IV: Four bar Mechanism for Four Coupler Positions Generation

Synthesis of Planar Mechanisms; Part IV: Four bar Mechanism for Four Coupler Positions Generation

Bultovic and Djordjevic (2004) studied the optimal synthesis of a 4-bar linkage by method of controlled deviation. They used the Hooke-Jeeves optimization technique without dependence on the initial selection of the projected variables [4]. Shiakolas, Koladiya and Kebrle (2005) presented a methodology combining different evolution, an evolutionary optimization and geometric control of precision positions for mechanism synthesis. They employed two penalty functions, one for constraint violation and one for relative accuracy [5]. Damangir, Jafarijashemi, Mamduhi and Zohoor (2006) proposed a curvature path description method for path generation of planar mechanisms. The objective function was independent of rotation and translation transformations [6]. Xi and Chen (2007) proposed an approach for the kinematic synthesis of a crank-rocker mechanism to generate a coupler motion passing through a prescribed set of positions [7]. Schrocker, Juttler and Agner (2008) presented an evolution based method for optimal mechanism synthesis. They used curve and surface evolution techniques from computer-aided design and image processing [8].

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USZEGED: Correction Type sensitive Normalization of English Tweets Using Efficiently Indexed n gram Statistics

USZEGED: Correction Type sensitive Normalization of English Tweets Using Efficiently Indexed n gram Statistics

Han and Baldwin (2011) rely on the identifica- tion of the words that require correction, then de- fine a confusion set containing the candidate IV correction forms for such words. Finally, a rank- ing scheme, taking multiple factors into consid- eration, is applied which selects the most likely correction for an OOV word. In their subsequent work, Han et al. (2012) propose an automated method to construct accurate normalization dictio- naries.

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The EU–Japan Economic Partnership Agreement  Bruegel Special Report, September 2018

The EU–Japan Economic Partnership Agreement Bruegel Special Report, September 2018

As discussed earlier, the EUJEPA is a comprehensive new generation trade agreement. However, in its simplest form, the largest degree of concessions on the Japanese side is a tariff reduction for what concerns food and wine, together with a recognition of Geographical Indications (GIs), while on the European side is an opening of its automotive market. This allows a rough estimate of the distribution of opportunities and threats from a European standpoint. Regarding the former, Table 6 represents a heat map based on the number of GIs possessed by each EU member state in both agricultural products, and alcoholic beverages. Based on this information, the countries that stand more ready to gain from the opportunities generated by the EUJEPA are Spain, France and Italy, followed by Germany and Portugal. This result confirms the model-based heterogeneity of impact presented in the previous section. Clearly, this analysis shows only the potential direct gains, and does not incorporate indirect effects and positive spillovers, which might well prove beneficial for the other Member States 26 .

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Isovitexin Exerts Anti-Inflammatory and Anti-Oxidant Activities on Lipopolysaccharide-Induced Acute Lung Injury by Inhibiting MAPK and NF-κB and Activating HO-1/Nrf2 Pathways

Isovitexin Exerts Anti-Inflammatory and Anti-Oxidant Activities on Lipopolysaccharide-Induced Acute Lung Injury by Inhibiting MAPK and NF-κB and Activating HO-1/Nrf2 Pathways

Based on the above outcome, we further inves- tigated whether the role played by IV in mice with LPS-induced ALI was protective. ALI, or ARDS, is characterized by inflammatory mediator release, lung edema, endothelial and epithelial cell integrity loss, and extensive neutrophil infiltration [48]. To assess histological changes after IV pretreatment in LPS-induced mice, lung sections were evaluated us- ing hematoxylin and eosin staining. We determined that both IV and Dex could ameliorate LPS-induced damage in lung tissues, including inflammatory cell infiltration and alveolar hemorrhage. On the other hand, recent report has suggested that the decreased BAL protein concentration and lung IL-6 secretion was related to the improvement of endothelial barrier function in LPS-induced ALI mice, and that the sup- pression of endothelial cell activation was associated with the inhibition of IL-6 in LPS-induced HPAECs [49]. Moreover, expression of ICAM-1 and VCAM-1, which are adhesion molecules, are essential for neu- trophil adhesion, migration and infiltration [50]. In this study, we demonstrated that IV reduced BAL protein concentration and lung IL-6 secretion, inhib- ited the LPS-induced IL-6 secretion in HPAECs and mice, and decreased the ICAM-1 and VCAM-1 pro- tein expression in the lung. Taken together, these findings illustrated that IV is a potential therapeutic role in ameliorating neutrophils adhesion and endo- thelial activation and endothelial barrier functions during ALI. Additionally, ALI leads to excessive macrophage activation and massive neutrophil ac- cumulation in the lungs; together, these responses can promote inflammatory cytokine release and enhance ROS generation [27, 51]. In the present study, IV and Dex both effectively decreased the numbers of total cells, neutrophils and macrophages in BALF. MPO, an enzyme that exists in azurophilic granules of naive PMNs, produces excess oxidants, resulting in tissue damage [52]. Furthermore, LPS instillation into the lungs can induce massive accumulation of ROS, in- creasing MDA levels. MDA is an end-product of lipid oxidation and therefore can serve to indicate cell membrane damage and destruction [53]. Our data illustrated that IV markedly decreased MPO and MDA levels in lung tissues exposed to LPS. Under unstressed conditions, this amelioration of oxidative injury is derived from the activities of antioxidative enzymes, including SOD and GSH. SOD can convert superoxide anions into hydrogen peroxide, which is then metabolized to water by CAT or GSH [54]. In our experiments, IV increased the activities of SOD and GSH in mice with LPS-induced ALI. Importantly, many recent studies have suggested that Nrf2 is es- sential for regulating oxidative stress and inflamma- tion in mice with LPS-induced ALI [55]. Moreover,

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Synthesis, Characterization and Antifungal Activity of 3 Substituted Triazipino [3,4 b] [1,3] Benzothiazole

Synthesis, Characterization and Antifungal Activity of 3 Substituted Triazipino [3,4 b] [1,3] Benzothiazole

Two moieties are fused and screened for antifungal studies they showed a broad spectrum of antifungal activity. They showed good activity against Penicillium sp and Aspergillus Niger species. 4-cyano-5-imino-3-methylthio-9- nitro-2H-1,2,4-triazepino [3,4-b] [1,3] benzo- thiazole (IV-46) and its 3-substituted derivatives are responsible for antifungal activity, but it is interesting to note that benzothiazole moieties when fused with other moieties showed a broad spectrum antifungal activity. Hence in search of new generation of antibiotics it may be worthwhile to explore the possibility in this area by fusing different moieties and increase potency.

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Green-Based Generation Expansion Planning For Kenya Using Wien Automatic Software Package (WASP) IV Model.

Green-Based Generation Expansion Planning For Kenya Using Wien Automatic Software Package (WASP) IV Model.

The world power generation sector is projected to undergo unprecedented demand growth from 17,408 TWh in 2004 to 33,750 TWh in 2030 at an average annual growth rate of 2.6%. To meet this demand, the sector will built 5,087GW of which over 75% will come from oil, coal and gas power plants. Consequently, the carbon-intensive plants are expected to rise the CO2 emissions from 9600-16400Mt at an annual growth rate of 2%. The rapidly increasing global emission is the major cause of global climate change [1]. Consequently, the global generation sector is faced with enormous pressure to lead the way in climate change mitigation strategies. Thus generation companies (GENCOs) in many countries in the world are currently planning towards environmentally-friendly generation investments [1], [2]. The most popular energy policy measure towards this course is the use of Renewable energy (RE) as suitable clean energy option to the conventional carbon intensive plants [3], [4]. Subsequently, more integration of RE in the power system’s least-cost generation expansion planning (GEP) is rapidly gaining extraordinary consideration as a sustainable option to security of power and CO2 emission reduction [5], [6]. The system integration also presents a significant potential for carbon credits as revenues in the generation sector from the carbon market [7], [8], [9]. Furthermore, other fringe benefits such as health benefits, green jobs and foreign exchange savings prevail for sustainable development [10], [11]. In Kenya, the generation sector prepares 20 year rolling least cost power development plan (LCPDP) at the energy regulatory commission (ERC) for expanding the power system to meet the current and future power demands. The 2011-2031 LCPDP under the focus of this study had projected a hydropower and heavy fuel oil (HFO) dominated power generation [12] that posed serious challenges. The hydros were vulnerable to acute energy shortfalls due to the frequent droughts. On the other hand, the HFO and the planned conventional coal plants posed the CO2 emissions dilemma [13], [14]. These were crucial issues for

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Computational methods of Gaussian Particle Swarm Optimization (GPSO) and Lagrange Multiplier on economic dispatch issues (case study on electrical system of Java-Bali IV area)

Computational methods of Gaussian Particle Swarm Optimization (GPSO) and Lagrange Multiplier on economic dispatch issues (case study on electrical system of Java-Bali IV area)

and development and can also be combined with other methods to further improve its performance. 2. Economic dispatch problems in this study can be extended to counting losses in power transmission, engine repairs and maintenance costs. Besides the objective function minimizes the total cost of fuel can be combined with the objective function to minimize pollutant emissions from the generation process.

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Preliminary analysis of the structural effects due to dynamic loads of the isolated next generation lead cooled reactor

Preliminary analysis of the structural effects due to dynamic loads of the isolated next generation lead cooled reactor

The carried out preliminary analysis is intended to evaluate firstly the influence of the dynamic loads inside a possible ELSY next generation isolated containment building and then the determined structural effects on the RV and its main internal components. Moreover because seismic load entails with possible structural effects as well as any consequent damages and economic losses, decreasing this intensity can result in a safely and better ELSY reactor design.

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SOLID WASTE MANAGEMENT

SOLID WASTE MANAGEMENT

The report is aimed to study the “Solid Waste Management” with emphasis on the following case study at “Rajahmundry”. Municipal solid waste (MSW), also called urban solid waste, is a waste type that includes predominantly household waste (domestic waste) with sometimes the addition of commercial wastes collected by a municipality within a given area. They are in either solid or semisolid form and generally exclude industrial hazardous wastes. The term residual waste relates to waste left from household sources containing materials that have not been separated out or sent for reprocessing. There are five broad categories include Biodegradable waste, Recyclable material, Inert waste, Composite wastes and Domestic Hazardous Waste. The elements of municipal solid waste involve i) Waste generation, ii) Waste handling and separation, storage and processing at the source, iii) Collection, iv) Separation and processing and transformation of solid wastes v) Transfer and transport vi) Disposal. The study overviews the various waste to disposal methods and various objectives to protect environment.

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Synthesis of wind time series for network adequacy assessment

Synthesis of wind time series for network adequacy assessment

A statistical model, alternatively, aims to synthesise wind time series from a set of equations which correctly charac- terise the auto-correlative nature of the wind resource, and potentially allowing the generation of much larger amounts of time series data than may exist in historical datasets. This can also greatly reduce the computational burden, by allowing wind power data to be created as it is required by a wider simulation, rather than having to handle and store data in bulk. However, in such approaches it is key that the temporal and spatial correlations of the natural resource are correctly characterised, in order that the variability of wind injections across an electrical network adequately captures the variety of likely operating states.

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