An Experiment on the Impact of Communication Problems in the Multi-cultural Operation of NPPs' Emergency Operation

Energy Technology Data Exchange (ETDEWEB)

Kang, Seongkeun; Lee, Chanyoung; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of); Ha, Jun Su [KUSTAR, Abu Dhabi (United Arab Emirates)

2015-10-15

Korean government won a contract of nuclear power plants to UAE government in 2010 and nuclear power plants are now under construction in Barakah, UAE. However, with technology transfer and international cooperation, there needs to consider several potential problems due to the differences between two culture of the countries such as language, technical culture and expectation. It is unknown how potential problems can lead to an unsafe plant operation as well. We got to know language problem is the main issue from analyzing the OERs. Korean nuclear power plant operators will work in UAE and they will operate the NPPs with other countries' operators and managers. Therefore they will have to use English when they communicate each other. The purpose of this paper is to confirm how much operators get stress and how much accuracy is declined when operators communicate together in English. Reducing human error is quite important to make nuclear power plants safety. As mental workload of human operator is increased, operators get more stress, then the probability of occurring human error may be increased. It will affect bad influence to nuclear power plants safety. There are many factors to make mental workload increased. We focused on communication problem which is a key factor of the increasing mental workload because many Korean operators will work in UAE nuclear power plants and they may work together with UAE operators. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To find the impact of how much English affects the operators' workload, we did two cases of experiments; one is experiment for diagnosis and the other is experiment for execution.

Some threshold spectral problems of Schroedinger operators

International Nuclear Information System (INIS)

Jia, X.

2009-01-01

This Ph.D. thesis deals with some spectral problems of the Schroedinger operators. We first consider the semi-classical limit of the number of bound states of unique two-cluster N-body Schroedinger operator. Then we use Dirichlet-Neumann bracket to get semi-classical limit of Riesz means of the discrete eigenvalues of N-body Schroedinger operator. The effective potential of N-body Schroedinger operator with Coulomb potential is also considered and we find that the effective potential has critical decay at infinity. Thus, the Schroedinger operator with critical potential is studied in this thesis. We study the coupling constant threshold of Schroedinger operator with critical potential and the asymptotic expansion of resolvent of Schroedinger operator with critical potential. We use that expansion to study low-energy asymptotics of derivative of spectral shift function for perturbation with critical decay. After that, we use this result and the known result for high-energy asymptotic expansion of spectral shift function to obtain the Levinson theorem. (author)

Some particular problems put by operating experimental reactors

International Nuclear Information System (INIS)

Candiotti, C.; Mabeix, R.; Uguen, R.

1960-01-01

On basis of a six years experience in operating research reactors, the authors explain, first, the difference in their utilization between these piles and another similar ones and, after, in consequence, they set off corresponding servitudes. These servitudes put very particular problems in operating itself, maintenance, modifications or additions on these apparatus. (author) [fr

Geostatistical regularization operators for geophysical inverse problems on irregular meshes

Science.gov (United States)

Jordi, C.; Doetsch, J.; Günther, T.; Schmelzbach, C.; Robertsson, J. OA

2018-05-01

Irregular meshes allow to include complicated subsurface structures into geophysical modelling and inverse problems. The non-uniqueness of these inverse problems requires appropriate regularization that can incorporate a priori information. However, defining regularization operators for irregular discretizations is not trivial. Different schemes for calculating smoothness operators on irregular meshes have been proposed. In contrast to classical regularization constraints that are only defined using the nearest neighbours of a cell, geostatistical operators include a larger neighbourhood around a particular cell. A correlation model defines the extent of the neighbourhood and allows to incorporate information about geological structures. We propose an approach to calculate geostatistical operators for inverse problems on irregular meshes by eigendecomposition of a covariance matrix that contains the a priori geological information. Using our approach, the calculation of the operator matrix becomes tractable for 3-D inverse problems on irregular meshes. We tested the performance of the geostatistical regularization operators and compared them against the results of anisotropic smoothing in inversions of 2-D surface synthetic electrical resistivity tomography (ERT) data as well as in the inversion of a realistic 3-D cross-well synthetic ERT scenario. The inversions of 2-D ERT and seismic traveltime field data with geostatistical regularization provide results that are in good accordance with the expected geology and thus facilitate their interpretation. In particular, for layered structures the geostatistical regularization provides geologically more plausible results compared to the anisotropic smoothness constraints.

Cost-effective computations with boundary interface operators in elliptic problems

International Nuclear Information System (INIS)

Khoromskij, B.N.; Mazurkevich, G.E.; Nikonov, E.G.

1993-01-01

The numerical algorithm for fast computations with interface operators associated with the elliptic boundary value problems (BVP) defined on step-type domains is presented. The algorithm is based on the asymptotically almost optimal technique developed for treatment of the discrete Poincare-Steklov (PS) operators associated with the finite-difference Laplacian on rectangles when using the uniform grid with a 'displacement by h/2'. The approach can be regarded as an extension of the method proposed for the partial solution of the finite-difference Laplace equation to the case of displaced grids and mixed boundary conditions. It is shown that the action of the PS operator for the Dirichlet problem and mixed BVP can be computed with expenses of the order of O(Nlog 2 N) both for arithmetical operations and computer memory needs, where N is the number of unknowns on the rectangle boundary. The single domain algorithm is applied to solving the multidomain elliptic interface problems with piecewise constant coefficients. The numerical experiments presented confirm almost linear growth of the computational costs and memory needs with respect to the dimension of the discrete interface problem. 14 refs., 3 figs., 4 tabs

The inverse spectral problem for pencils of differential operators

International Nuclear Information System (INIS)

Guseinov, I M; Nabiev, I M

2007-01-01

The inverse problem of spectral analysis for a quadratic pencil of Sturm-Liouville operators on a finite interval is considered. A uniqueness theorem is proved, a solution algorithm is presented, and sufficient conditions for the solubility of the inverse problem are obtained. Bibliography: 31 titles.

The operational flight and multi-crew scheduling problem

Directory of Open Access Journals (Sweden)

Stojković Mirela

2005-01-01

Full Text Available This paper introduces a new kind of operational multi-crew scheduling problem which consists in simultaneously modifying, as necessary, the existing flight departure times and planned individual work days (duties for the set of crew members, while respecting predefined aircraft itineraries. The splitting of a planned crew is allowed during a day of operations, where it is more important to cover a flight than to keep planned crew members together. The objective is to cover a maximum number of flights from a day of operations while minimizing changes in both the flight schedule and the next-day planned duties for the considered crew members. A new type of the same flight departure time constraints is introduced. They ensure that a flight which belongs to several personalized duties, where the number of duties is equal to the number of crew members assigned to the flight, will have the same departure time in each of these duties. Two variants of the problem are considered. The first variant allows covering of flights by less than the planned number of crew members, while the second one requires covering of flights by a complete crew. The problem is mathematically formulated as an integer nonlinear multi-commodity network flow model with time windows and supplementary constraints. The optimal solution approach is based on Dantzig-Wolfe decomposition/column generation embedded into a branch-and-bound scheme. The resulting computational times on commercial-size problems are very good. Our new simultaneous approach produces solutions whose quality is far better than that of the traditional sequential approach where the flight schedule has been changed first and then input as a fixed data to the crew scheduling problem.

Applications of systems thinking and soft operations research in managing complexity from problem framing to problem solving

CERN Document Server

2016-01-01

This book captures current trends and developments in the field of systems thinking and soft operations research which can be applied to solve today's problems of dynamic complexity and interdependency. Such ‘wicked problems’ and messes are seemingly intractable problems characterized as value-laden, ambiguous, and unstable, that resist being tamed by classical problem solving. Actions and interventions associated with this complex problem space can have highly unpredictable and unintended consequences. Examples of such complex problems include health care reform, global climate change, transnational serious and organized crime, terrorism, homeland security, human security, disaster management, and humanitarian aid. Moving towards the development of solutions to these complex problem spaces depends on the lens we use to examine them and how we frame the problem. It will be shown that systems thinking and soft operations research has had great success in contributing to the management of complexity. .

Nuclear graphite development, operational problems, and resolution of these problems at the Hanford production reactors

International Nuclear Information System (INIS)

Morgan, W.C.

1996-01-01

This paper chronicles the history of the Hanford Production Reactor, from the initial design considerations for B, D, and F Reactors through the selection of the agreed method for safe disposal of the decommissioned reactors. The operational problems that challenged the operations and support staff of each new generation of production reactors, the engineering actions an operational changes that alleviated or resolved the immediate problems, the changes in reactor design and design-bases for the next generation of production reactors, and the changes in manufacturing variables that resulted in new ''improved'' grades of nuclear graphites for use in the moderators of the Hanford Production Reactors are reviewed in the context of the existing knowledge-base and the mission-driven priorities on the time. 14 refs, 6 figs, 3 tabs

The Convergence Problems of Eigenfunction Expansions of Elliptic Differential Operators

Science.gov (United States)

Ahmedov, Anvarjon

2018-03-01

In the present research we investigate the problems concerning the almost everywhere convergence of multiple Fourier series summed over the elliptic levels in the classes of Liouville. The sufficient conditions for the almost everywhere convergence problems, which are most difficult problems in Harmonic analysis, are obtained. The methods of approximation by multiple Fourier series summed over elliptic curves are applied to obtain suitable estimations for the maximal operator of the spectral decompositions. Obtaining of such estimations involves very complicated calculations which depends on the functional structure of the classes of functions. The main idea on the proving the almost everywhere convergence of the eigenfunction expansions in the interpolation spaces is estimation of the maximal operator of the partial sums in the boundary classes and application of the interpolation Theorem of the family of linear operators. In the present work the maximal operator of the elliptic partial sums are estimated in the interpolation classes of Liouville and the almost everywhere convergence of the multiple Fourier series by elliptic summation methods are established. The considering multiple Fourier series as an eigenfunction expansions of the differential operators helps to translate the functional properties (for example smoothness) of the Liouville classes into Fourier coefficients of the functions which being expanded into such expansions. The sufficient conditions for convergence of the multiple Fourier series of functions from Liouville classes are obtained in terms of the smoothness and dimensions. Such results are highly effective in solving the boundary problems with periodic boundary conditions occurring in the spectral theory of differential operators. The investigations of multiple Fourier series in modern methods of harmonic analysis incorporates the wide use of methods from functional analysis, mathematical physics, modern operator theory and spectral

Genetic Algorithm for Traveling Salesman Problem with Modified Cycle Crossover Operator

Directory of Open Access Journals (Sweden)

Abid Hussain

2017-01-01

Full Text Available Genetic algorithms are evolutionary techniques used for optimization purposes according to survival of the fittest idea. These methods do not ensure optimal solutions; however, they give good approximation usually in time. The genetic algorithms are useful for NP-hard problems, especially the traveling salesman problem. The genetic algorithm depends on selection criteria, crossover, and mutation operators. To tackle the traveling salesman problem using genetic algorithms, there are various representations such as binary, path, adjacency, ordinal, and matrix representations. In this article, we propose a new crossover operator for traveling salesman problem to minimize the total distance. This approach has been linked with path representation, which is the most natural way to represent a legal tour. Computational results are also reported with some traditional path representation methods like partially mapped and order crossovers along with new cycle crossover operator for some benchmark TSPLIB instances and found improvements.

Active Learning with Rationales for Identifying Operationally Significant Anomalies in Aviation

Science.gov (United States)

Sharma, Manali; Das, Kamalika; Bilgic, Mustafa; Matthews, Bryan; Nielsen, David Lynn; Oza, Nikunj C.

2016-01-01

A major focus of the commercial aviation community is discovery of unknown safety events in flight operations data. Data-driven unsupervised anomaly detection methods are better at capturing unknown safety events compared to rule-based methods which only look for known violations. However, not all statistical anomalies that are discovered by these unsupervised anomaly detection methods are operationally significant (e.g., represent a safety concern). Subject Matter Experts (SMEs) have to spend significant time reviewing these statistical anomalies individually to identify a few operationally significant ones. In this paper we propose an active learning algorithm that incorporates SME feedback in the form of rationales to build a classifier that can distinguish between uninteresting and operationally significant anomalies. Experimental evaluation on real aviation data shows that our approach improves detection of operationally significant events by as much as 75% compared to the state-of-the-art. The learnt classifier also generalizes well to additional validation data sets.

Experiments on the Impact of language Problems in the Multi-cultural Operation of NPPs' Emergency Operation

International Nuclear Information System (INIS)

Kang, Seongkeun; Kim, Taehoon; Seong, Poong Hyun; Ha, Jun Su

2016-01-01

In 2010, The Korea Electric Power Corporation (KEPCO) was awarded a multi-billion dollar bid to construct the first nuclear power plant in Barakah, UAE. One must keep in mind however, that with technology transfer and international cooperation comes a host of potential problems arising from cultural differences such as language, everyday habitudes and workplace expectation. As of now, how problematic these potential issues may become is unknown. Of the aforementioned factors, communication is perhaps of foremost importance. We investigated UAE culture-related issues through analysis of operating experience reviews (OERs) and came to the conclusion that the language barrier needed utmost attention. Korean nuclear power plant operators will work in UAE and will operate the NPPs with operators and managers of other nationalities as well. The purpose of this paper is firstly to confirm that operators are put under mental stress, and secondly to demonstrate the decline in accuracy when they must work in English. Reducing human error is quite important to make nuclear power plants safer. As the mental workload of human operator is increased, the probability of a human error occurring also increases. It will have a negative influence on the plant’s safety. There are many factors which can potentially increase mental workload. We focused on communication problem which is a key factor of increasing mental workload because many Korean operators will work in UAE nuclear power plants and may work together with UAE operators. From these experiments we compared how performance of both Korean and UAE subjects were decreased when they use English. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To

Effect of operative treatment on psychosocial problems of men with gynaecomastia.

Science.gov (United States)

Kasielska, Anna; Antoszewski, Bogusław

2011-11-01

Gynaecomastia is defined as a hyperplasia of the breast tissue in men, bilateral or unilateral, usually not associated with the presence of malignant lesions.The aim of the study was to explore the psychosocial problems of men with gynecomastia and the effect of operative breast reduction on these problems.Material and methods. The survey was conducted in a group of 47 men who were treated surgically for gynaecomastia in the Department of Plastic, Reconstructive and Aesthetic Surgery. The mean age of the respondents was 25.6±3.5 years. For survey purposes, a questionnaire was developed with questions about the age of onset of gynaecomastia, coexisting disorders and medicines taken and also various aspects of the psychosocial life of the respondents. The questionnaire was completed by patients before surgery and at minimum 6 months after surgery.Results. The findings showed that in almost all patients gynaecomastia had caused emotional discomfort and limitation of everyday activity. In many patients, enlarged breasts caused difficulties in entering into social relationships. More than a half of the surveyed men admitted that their problems were ridiculed by others and they felt isolated. A comparison of the respondents' answers before and after the surgery showed statistically significant differences in all of the analysed questionnaire items.Conclusions. Gynaecomastia causes considerable emotional discomfort and limitation of everyday activity in young men, and that is why it constitutes a psychosocial problem. Surgical treatment of gynaecomastia significantly contributes to an increase in social activity and an improvement of social acceptance and emotional comfort, and thus significantly improves satisfaction from personal life in the men who underwent this intervention.

Numerical Solution of Time-Dependent Problems with a Fractional-Power Elliptic Operator

Science.gov (United States)

Vabishchevich, P. N.

2018-03-01

A time-dependent problem in a bounded domain for a fractional diffusion equation is considered. The first-order evolution equation involves a fractional-power second-order elliptic operator with Robin boundary conditions. A finite-element spatial approximation with an additive approximation of the operator of the problem is used. The time approximation is based on a vector scheme. The transition to a new time level is ensured by solving a sequence of standard elliptic boundary value problems. Numerical results obtained for a two-dimensional model problem are presented.

A problem-solving routine for improving hospital operations.

Science.gov (United States)

Ghosh, Manimay; Sobek Ii, Durward K

2015-01-01

The purpose of this paper is to examine empirically why a systematic problem-solving routine can play an important role in the process improvement efforts of hospitals. Data on 18 process improvement cases were collected through semi-structured interviews, reports and other documents, and artifacts associated with the cases. The data were analyzed using a grounded theory approach. Adherence to all the steps of the problem-solving routine correlated to greater degrees of improvement across the sample. Analysis resulted in two models. The first partially explains why hospital workers tended to enact short-term solutions when faced with process-related problems; and tended not seek longer-term solutions that prevent problems from recurring. The second model highlights a set of self-reinforcing behaviors that are more likely to address problem recurrence and result in sustained process improvement. The study was conducted in one hospital setting. Hospital managers can improve patient care and increase operational efficiency by adopting and diffusing problem-solving routines that embody three key characteristics. This paper offers new insights on why caregivers adopt short-term approaches to problem solving. Three characteristics of an effective problem-solving routine in a healthcare setting are proposed.

An inverse boundary value problem for the Schroedinger operator with vector potentials in two dimensions

International Nuclear Information System (INIS)

Ziqi Sun

1993-01-01

During the past few years a considerable interest has been focused on the inverse boundary value problem for the Schroedinger operator with a scalar (electric) potential. The popularity gained by this subject seems to be due to its connection with the inverse scattering problem at fixed energy, the inverse conductivity problem and other important inverse problems. This paper deals with an inverse boundary value problem for the Schroedinger operator with vector (electric and magnetic) potentials. As in the case of the scalar potential, results of this study would have immediate consequences in the inverse scattering problem for magnetic field at fixed energy. On the other hand, inverse boundary value problems for elliptic operators are of independent interest. The study is partly devoted to the understanding of the inverse boundary value problem for a class of general elliptic operator of second order. Note that a self-adjoint elliptic operator of second order with Δ as its principal symbol can always be written as a Schroedinger operator with vector potentials

A Posteriori Analysis of Adaptive Multiscale Operator Decomposition Methods for Multiphysics Problems

Energy Technology Data Exchange (ETDEWEB)

Donald Estep; Michael Holst; Simon Tavener

2010-02-08

This project was concerned with the accurate computational error estimation for numerical solutions of multiphysics, multiscale systems that couple different physical processes acting across a large range of scales relevant to the interests of the DOE. Multiscale, multiphysics models are characterized by intimate interactions between different physics across a wide range of scales. This poses significant computational challenges addressed by the proposal, including: (1) Accurate and efficient computation; (2) Complex stability; and (3) Linking different physics. The research in this project focused on Multiscale Operator Decomposition methods for solving multiphysics problems. The general approach is to decompose a multiphysics problem into components involving simpler physics over a relatively limited range of scales, and then to seek the solution of the entire system through some sort of iterative procedure involving solutions of the individual components. MOD is a very widely used technique for solving multiphysics, multiscale problems; it is heavily used throughout the DOE computational landscape. This project made a major advance in the analysis of the solution of multiscale, multiphysics problems.

Specific problems in Kozloduy municipality, concerning NPP operation and decommissioning

International Nuclear Information System (INIS)

Pironkova, L.

2000-01-01

The only nuclear power plant in Bulgaria, which operates for 25 years is located in Kozloduy. Kozloduy municipality is situated in the northern part of Danube plane, includes the administrative center and four villages. It is 200 km far from Sofia and 80 km from the regional center Vratza. The Kozloduy NPP operates 6 units of total capacity 3760 MW, producing more than 40% of the electricity needs in Bulgaria. Settled and recurring problems of the municipality are related to economic, geographical, demographic and administration issues. Future problems will be related to forthcoming reactor shutdown and decommissioning. This involves economic problems, possible bankruptcies of local firms servicing the NPP, decreasing budget and living standard, expected restrictions of social programs, increasing unemployment, possible changes in demographic structure of population

Experiments on the Impact of language Problems in the Multi-cultural Operation of NPPs' Emergency Operation

Energy Technology Data Exchange (ETDEWEB)

Kang, Seongkeun; Kim, Taehoon; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of); Ha, Jun Su [KUSTAR, Abu Dhabi (United Arab Emirates)

2016-10-15

In 2010, The Korea Electric Power Corporation (KEPCO) was awarded a multi-billion dollar bid to construct the first nuclear power plant in Barakah, UAE. One must keep in mind however, that with technology transfer and international cooperation comes a host of potential problems arising from cultural differences such as language, everyday habitudes and workplace expectation. As of now, how problematic these potential issues may become is unknown. Of the aforementioned factors, communication is perhaps of foremost importance. We investigated UAE culture-related issues through analysis of operating experience reviews (OERs) and came to the conclusion that the language barrier needed utmost attention. Korean nuclear power plant operators will work in UAE and will operate the NPPs with operators and managers of other nationalities as well. The purpose of this paper is firstly to confirm that operators are put under mental stress, and secondly to demonstrate the decline in accuracy when they must work in English. Reducing human error is quite important to make nuclear power plants safer. As the mental workload of human operator is increased, the probability of a human error occurring also increases. It will have a negative influence on the plant’s safety. There are many factors which can potentially increase mental workload. We focused on communication problem which is a key factor of increasing mental workload because many Korean operators will work in UAE nuclear power plants and may work together with UAE operators. From these experiments we compared how performance of both Korean and UAE subjects were decreased when they use English. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To

Automatic Combination of Operators in a Genetic Algorithm to Solve the Traveling Salesman Problem.

Directory of Open Access Journals (Sweden)

Carlos Contreras-Bolton

Full Text Available Genetic algorithms are powerful search methods inspired by Darwinian evolution. To date, they have been applied to the solution of many optimization problems because of the easy use of their properties and their robustness in finding good solutions to difficult problems. The good operation of genetic algorithms is due in part to its two main variation operators, namely, crossover and mutation operators. Typically, in the literature, we find the use of a single crossover and mutation operator. However, there are studies that have shown that using multi-operators produces synergy and that the operators are mutually complementary. Using multi-operators is not a simple task because which operators to use and how to combine them must be determined, which in itself is an optimization problem. In this paper, it is proposed that the task of exploring the different combinations of the crossover and mutation operators can be carried out by evolutionary computing. The crossover and mutation operators used are those typically used for solving the traveling salesman problem. The process of searching for good combinations was effective, yielding appropriate and synergic combinations of the crossover and mutation operators. The numerical results show that the use of the combination of operators obtained by evolutionary computing is better than the use of a single operator and the use of multi-operators combined in the standard way. The results were also better than those of the last operators reported in the literature.

Problem Sets: Fundamentals Of Transportation And Traffic Operations

OpenAIRE

Daganzo, Carlos F.

1998-01-01

These problem sets comprise a supplement to Fundamentals of Transportation and Traffic Operations (C. Daganzo, Pergamon, 1997). Academicians can also obtain a companion set of solutions by writing to "Institute of Transportation Studies, Publications Office, 109 McLaughlin Hall, University of California, Berkeley, CA 94720" or by sending e-mail to .

Problem-Based Learning for Production and Operations Management

Science.gov (United States)

Kanet, John J.; Barut, Mehmet

2003-01-01

In this paper, we describe our application of "problem-based learning" in the teaching of production/operations management. We describe a study of the effectiveness of this approach and present the results and analysis of this study. We provide a collection of our experiences in using this method and conclude with some general…

An abstract approach to some spectral problems of direct sum differential operators

Directory of Open Access Journals (Sweden)

Maksim S. Sokolov

2003-07-01

Full Text Available In this paper, we study the common spectral properties of abstract self-adjoint direct sum operators, considered in a direct sum Hilbert space. Applications of such operators arise in the modelling of processes of multi-particle quantum mechanics, quantum field theory and, specifically, in multi-interval boundary problems of differential equations. We show that a direct sum operator does not depend in a straightforward manner on the separate operators involved. That is, on having a set of self-adjoint operators giving a direct sum operator, we show how the spectral representation for this operator depends on the spectral representations for the individual operators (the coordinate operators involved in forming this sum operator. In particular it is shown that this problem is not immediately solved by taking a direct sum of the spectral properties of the coordinate operators. Primarily, these results are to be applied to operators generated by a multi-interval quasi-differential system studied, in the earlier works of Ashurov, Everitt, Gesztezy, Kirsch, Markus and Zettl. The abstract approach in this paper indicates the need for further development of spectral theory for direct sum differential operators.

A fast method for the unit scheduling problem with significant renewable power generation

International Nuclear Information System (INIS)

Osório, G.J.; Lujano-Rojas, J.M.; Matias, J.C.O.; Catalão, J.P.S.

2015-01-01

Highlights: • A model to the scheduling of power systems with significant renewable power generation is provided. • A new methodology that takes information from the analysis of each scenario separately is proposed. • Based on a probabilistic analysis, unit scheduling and corresponding economic dispatch are estimated. • A comparison with others methodologies is in favour of the proposed approach. - Abstract: Optimal operation of power systems with high integration of renewable power sources has become difficult as a consequence of the random nature of some sources like wind energy and photovoltaic energy. Nowadays, this problem is solved using Monte Carlo Simulation (MCS) approach, which allows considering important statistical characteristics of wind and solar power production such as the correlation between consecutive observations, the diurnal profile of the forecasted power production, and the forecasting error. However, MCS method requires the analysis of a representative amount of trials, which is an intensive calculation task that increases considerably with the number of scenarios considered. In this paper, a model to the scheduling of power systems with significant renewable power generation based on scenario generation/reduction method, which establishes a proportional relationship between the number of scenarios and the computational time required to analyse them, is proposed. The methodology takes information from the analysis of each scenario separately to determine the probabilistic behaviour of each generator at each hour in the scheduling problem. Then, considering a determined significance level, the units to be committed are selected and the load dispatch is determined. The proposed technique was illustrated through a case study and the comparison with stochastic programming approach was carried out, concluding that the proposed methodology can provide an acceptable solution in a reduced computational time

Metropolis Parking Problems and Management Planning Solutions for Traffic Operation Effectiveness

Directory of Open Access Journals (Sweden)

Yuejun Liu

2012-01-01

Full Text Available Advances in mobility are clearly illustrated by the rapid development of urbanization and motorization in developing countries. Following the dramatic incensement of traffic demand, the parking problem has been becoming much more seriously important in many metropolises. With the aim of seeking solutions as to how the parking system could operate more efficiently by using new technologies and new methodologies, this paper discusses the application of geographic information system into the parking planning and management for traffic operation effectiveness in metropolis. The concentration of this paper includes the characteristics of parking demand and the causations of parking problems, especially the basic parking principle and strategies for solving parking problems from the perspective of geographic information system are discussed in enough detail in this paper.

Analysis of Pending Problems for a Technology Demand of Domestic Operational Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Koo, Dae Seo; Park, Won Seok; Wi, Myung Hwan; Ha, Jae Joo

2008-01-15

Eleven technology fields were chosen, which have a relation with the solution of the pending problems of domestic operational nuclear power plants to manage an efficient operation and safe regulation for domestic nuclear power plants. The progressive background, requirements, and performance on the pending problems, 34, of an operation and regulation for domestic nuclear power plants were analyzed with regard to a risk information application, severe accident, PSR of structural materials, underwater monitoring, operation inspection and a fire protection, an instrument aging, metal integrity and steam generator, human technology and a digital I and C, quality assurance, secondary system and a user reliance and mass communications. KAERI's role is to provide a solution to these pending problems of domestic nuclear power plants. KAERI's technology is to be applicable to the pending problems for domestic nuclear power plants to raise an operational efficiency and an application frequency of nuclear power plants. In the future, a technology treaty between KAERI and KHNP is to be established to solve the pending problems for domestic nuclear power plants. Operation rate of nuclear power plants will also be raised and contribute to the supply of national energy due to this technology treaty.

The motivating operation and negatively reinforced problem behavior: a systematic review.

Science.gov (United States)

Langthorne, Paul; McGill, Peter; Oliver, Chris

2014-01-01

The concept of motivational operations exerts an increasing influence on the understanding and assessment of problem behavior in people with intellectual and developmental disability. In this systematic review of 59 methodologically robust studies of the influence of motivational operations in negative reinforcement paradigms in this population, we identify themes related to situational and biological variables that have implications for assessment, intervention, and further research. There is now good evidence that motivational operations of differing origins influence negatively reinforced problem behavior, and that these might be subject to manipulation to facilitate favorable outcomes. There is also good evidence that some biological variables warrant consideration in assessment procedures as they predispose the person's behavior to be influenced by specific motivational operations. The implications for assessment and intervention are made explicit with reference to variables that are open to manipulation or that require further research and conceptualization within causal models.

A bankruptcy problem approach to load-shedding in multiagent-based microgrid operation.

Science.gov (United States)

Kim, Hak-Man; Kinoshita, Tetsuo; Lim, Yujin; Kim, Tai-Hoon

2010-01-01

A microgrid is composed of distributed power generation systems (DGs), distributed energy storage devices (DSs), and loads. To maintain a specific frequency in the islanded mode as an important requirement, the control of DGs' output and charge action of DSs are used in supply surplus conditions and load-shedding and discharge action of DSs are used in supply shortage conditions. Recently, multiagent systems for autonomous microgrid operation have been studied. Especially, load-shedding, which is intentional reduction of electricity use, is a critical problem in islanded microgrid operation based on the multiagent system. Therefore, effective schemes for load-shedding are required. Meanwhile, the bankruptcy problem deals with dividing short resources among multiple agents. In order to solve the bankruptcy problem, division rules, such as the constrained equal awards rule (CEA), the constrained equal losses rule (CEL), and the random arrival rule (RA), have been used. In this paper, we approach load-shedding as a bankruptcy problem. We compare load-shedding results by above-mentioned rules in islanded microgrid operation based on wireless sensor network (WSN) as the communication link for an agent's interactions.

Problems with veteran-family communication during operation enduring freedom/operation Iraqi freedom military deployment.

Science.gov (United States)

Hinojosa, Ramon; Hinojosa, Melanie Sberna; Högnäs, Robin S

2012-02-01

Twenty Reserve component (Army and Marines) and Army National Guard male veterans of Operational Enduring Freedom/Operation Iraqi Freedom discuss their deployment and postdeployment family reintegration experiences. A Grounded Theory approach is used to highlight some of the ways in which family miscommunication during deployment can occur. Communication with civilian family members is affected by the needs of operational security, technical problems with communication tools, miscommunication between family members, or because veterans have "nothing new to say" to family back home. These communication difficulties may lead to an initial gulf of understanding between veterans and family members that can cause family strain during postdeployment family reintegration. We end with a discussion of veteran family reintegration difficulties.

IE Information No. 86-71: Recent identified problems with Limitorque motor operators

International Nuclear Information System (INIS)

Jordan, E.L.

1992-01-01

This notice is provided to alert recipients of two potential problems discovered with Limitorque motor operators. On November 8, 1985 Georgia Power Company submitted a preliminary report to the NRC indicating that it had discovered burn damage to internal wiring in several Limitorque motor operators installed in their Vogtle Unit 1 Power Plant. On March 20, 1986 Georgia Power Company submitted a final report to the NRC which suggested that the burn damage was a generic problem applicable to all Limitorque motor operators. This assumption was based on a sampling inspection of 104 Limitorque motor operators installed in Vogtle Unit 1. Forty-six of the motor operators examined were Limitorque type SMB-000, and six of these were found to have burnt internal wiring. Out of the 58 operators other than type SMB-000 which were inspected, 5 were found to contain wires deemed susceptible to damage because of their close proximity to the heater elements (less than 1/2 inch). Several licensees have submitted reports to the NRC concerning a problem with cracked limit switch rotors on Limitorque motor operators installed inside and outside of containment. The limit switches are used for control of the motor operator and also provide indication of valve position in the control room. The cracks have been found on white melamine limit switch rotors. Most of these cracks were found in the area where the limit switch rotors are pinned to the pinion shafts. Some cracks have been found to extend halfway through the melamine rotors, weakening them to the extent that they are easily broken

A knowledge acquisition process to analyse operational problems in solid waste management facilities.

Science.gov (United States)

Dokas, Ioannis M; Panagiotakopoulos, Demetrios C

2006-08-01

The available expertise on managing and operating solid waste management (SWM) facilities varies among countries and among types of facilities. Few experts are willing to record their experience, while few researchers systematically investigate the chains of events that could trigger operational failures in a facility; expertise acquisition and dissemination, in SWM, is neither popular nor easy, despite the great need for it. This paper presents a knowledge acquisition process aimed at capturing, codifying and expanding reliable expertise and propagating it to non-experts. The knowledge engineer (KE), the person performing the acquisition, must identify the events (or causes) that could trigger a failure, determine whether a specific event could trigger more than one failure, and establish how various events are related among themselves and how they are linked to specific operational problems. The proposed process, which utilizes logic diagrams (fault trees) widely used in system safety and reliability analyses, was used for the analysis of 24 common landfill operational problems. The acquired knowledge led to the development of a web-based expert system (Landfill Operation Management Advisor, http://loma.civil.duth.gr), which estimates the occurrence possibility of operational problems, provides advice and suggests solutions.

A Bankruptcy Problem Approach to Load-shedding in Multiagent-based Microgrid Operation

Directory of Open Access Journals (Sweden)

Yujin Lim

2010-09-01

Full Text Available A microgrid is composed of distributed power generation systems (DGs, distributed energy storage devices (DSs, and loads. To maintain a specific frequency in the islanded mode as an important requirement,  the control of DGs’ output and charge action of DSs are used in supply surplus conditions and load-shedding and discharge action of DSs are used in supply shortage conditions. Recently, multiagent systems for autonomous microgrid operation have been studied. Especially, load-shedding, which is intentional reduction of electricity use, is a critical problem in islanded microgrid operation based on the multiagent system. Therefore, effective schemes for load-shedding are required. Meanwhile, the bankruptcy problem deals with dividing short resources among multiple agents. In order to solve the bankruptcy problem, division rules, such as the constrained equal awards rule (CEA, the constrained equal losses rule (CEL, and the random arrival rule (RA, have been used. In this paper, we approach load-shedding as a bankruptcy problem. We compare load-shedding results by above-mentioned rules in islanded microgrid operation based on wireless sensor network (WSN as the communication link for an agent’s interactions.

Factorization, Singular Operators and Related Problems : Conference in Honour of Professor Georgii Litvinchuk

CERN Document Server

Lebre, Amarino; Santos, António

2003-01-01

These proceedings comprise a large part of the papers presented at the International Conference Factorization, Singular Operators and related problems, which was held from January 28 to February 1, 2002, at the University of th Madeira, Funchal, Portugal, to mark Professor Georgii Litvinchuk's 70 birth­ day. Experts in a variety of fields came to this conference to pay tribute to the great achievements of Professor Georgii Litvinchuk in the development of vari­ ous areas of operator theory. The main themes of the conference were focussed around the theory of singular type operators and factorization problems, but other topics such as potential theory and fractional calculus, to name but a couple, were also presented. The goal of the conference was to bring together mathematicians from var­ ious fields within operator theory and function theory in order to highlight recent advances in problems many of which were originally studied by Profes­ sor Litvinchuk and his scientific school. A second aim was to sti...

Quadratic stochastic operators: Results and open problems

International Nuclear Information System (INIS)

Ganikhodzhaev, R.N.; Rozikov, U.A.

2009-03-01

The history of the quadratic stochastic operators can be traced back to the work of S. Bernshtein (1924). For more than 80 years this theory has been developed and many papers were published. In recent years it has again become of interest in connection with numerous applications in many branches of mathematics, biology and physics. But most results of the theory were published in non English journals, full text of which are not accessible. In this paper we give a brief description of the results and discuss several open problems. (author)

Gambling frequency, gambling problems and concerned significant others of problem gamblers in Finland: cross-sectional population studies in 2007 and 2011.

Science.gov (United States)

Salonen, Anne H; Alho, Hannu; Castrén, Sari

2015-05-01

This study compares past-year gambling frequency, gambling problems and concerned significant others (CSOs) of problem gamblers in Finland by age, from 2007 and 2011. We used random sample data collected in 2007 (n = 4722) and 2011 (n = 4484). The data were weighted, based on gender, age and region of residence. We measured the past-year gambling frequency using a categorical variable, while gambling severity was measured with the South Oaks Gambling Screen. We identified CSOs by a single question including seven response options. Chi-Squared and Fisher's exact tests were used. Overall, the past-year gambling frequency change was statistically significant between 2007 and 2011. Among 18-64-year-old Finnish people, the proportion of non-gamblers decreased. Yet, among 15-17-year-old respondents, non-gambling increased and gambling problems decreased. Among 18-24 year olds, the proportion of close ones with gambling problems also decreased. On the other hand, the proportion of family members with gambling problems increased among the 50-64 year olds. The increase in adult gambling participation was mainly explained by infrequent gambling. The proportion of gambling problems from the gamblers' and CSOs' perspective remained unchanged, yet significant changes were observed within age groups. The short-term changes in under-age gambling problems were desirable. Future studies should explore the adaptation and access hypotheses alongside gambling problems. © 2015 the Nordic Societies of Public Health.

Application of Operational Research Techniques in Operating Room Scheduling Problems: Literature Overview

Directory of Open Access Journals (Sweden)

Şeyda Gür

2018-01-01

Full Text Available Increased healthcare costs are pushing hospitals to reduce costs and increase the quality of care. Operating rooms are the most important source of income and expense for hospitals. Therefore, the hospital management focuses on the effectiveness of schedules and plans. This study includes analyses of recent research on operating room scheduling and planning. Most studies in the literature, from 2000 to the present day, were evaluated according to patient characteristics, performance measures, solution techniques used in the research, the uncertainty of the problem, applicability of the research, and the planning strategy to be dealt within the solution. One hundred seventy studies were examined in detail, after scanning the Emerald, Science Direct, JSTOR, Springer, Taylor and Francis, and Google Scholar databases. To facilitate the identification of these studies, they are grouped according to the different criteria of concern and then, a detailed overview is presented.

Computational approach to Thornley's problem by bivariate operational calculus

Science.gov (United States)

Bazhlekova, E.; Dimovski, I.

2012-10-01

Thornley's problem is an initial-boundary value problem with a nonlocal boundary condition for linear onedimensional reaction-diffusion equation, used as a mathematical model of spiral phyllotaxis in botany. Applying a bivariate operational calculus we find explicit representation of the solution, containing two convolution products of special solutions and the arbitrary initial and boundary functions. We use a non-classical convolution with respect to the space variable, extending in this way the classical Duhamel principle. The special solutions involved are represented in the form of fast convergent series. Numerical examples are considered to show the application of the present technique and to analyze the character of the solution.

On a non classical oblique derivative problem for parabolic singular integro-differential operators

International Nuclear Information System (INIS)

Nguyen Minh Chuong; Le Quang Trung

1989-10-01

In this paper an oblique derivative problem for parabolic singular integro-differential operators was studied. In this problem the direction of the derivative may be tangent to the boundary of the domain. By the large parameter method theorems of existence and uniqueness of solutions of the problem were obtained. (author). 10 refs

Performance impact of mutation operators of a subpopulation-based genetic algorithm for multi-robot task allocation problems.

Science.gov (United States)

Liu, Chun; Kroll, Andreas

2016-01-01

Multi-robot task allocation determines the task sequence and distribution for a group of robots in multi-robot systems, which is one of constrained combinatorial optimization problems and more complex in case of cooperative tasks because they introduce additional spatial and temporal constraints. To solve multi-robot task allocation problems with cooperative tasks efficiently, a subpopulation-based genetic algorithm, a crossover-free genetic algorithm employing mutation operators and elitism selection in each subpopulation, is developed in this paper. Moreover, the impact of mutation operators (swap, insertion, inversion, displacement, and their various combinations) is analyzed when solving several industrial plant inspection problems. The experimental results show that: (1) the proposed genetic algorithm can obtain better solutions than the tested binary tournament genetic algorithm with partially mapped crossover; (2) inversion mutation performs better than other tested mutation operators when solving problems without cooperative tasks, and the swap-inversion combination performs better than other tested mutation operators/combinations when solving problems with cooperative tasks. As it is difficult to produce all desired effects with a single mutation operator, using multiple mutation operators (including both inversion and swap) is suggested when solving similar combinatorial optimization problems.

Some particular problems put by operating experimental reactors; Quelques problemes particuliers poses par le fonctionnement des piles laboratoires

Energy Technology Data Exchange (ETDEWEB)

Candiotti, C; Mabeix, R; Uguen, R [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

On basis of a six years experience in operating research reactors, the authors explain, first, the difference in their utilization between these piles and another similar ones and, after, in consequence, they set off corresponding servitudes. These servitudes put very particular problems in operating itself, maintenance, modifications or additions on these apparatus. (author) [French] Les redacteurs se basant sur six annees d'experience dans l'exploitation de reacteurs de recherche, exposent tout d'abord les differences d'utilisation entre ces engins et d'autres appareils fonctionnellement similaires et font ressortir, par voie de consequence, les servitudes correspondantes. Ces servitudes posent des problemes tres particuliers dans les domaines de l'exploitation proprement dite, de l'entretien, des modifications ou adjonctions apportees a l'ensemble. (auteur)

Well-Posedness of Nonlocal Parabolic Differential Problems with Dependent Operators

Directory of Open Access Journals (Sweden)

Allaberen Ashyralyev

2014-01-01

Full Text Available The nonlocal boundary value problem for the parabolic differential equation v'(t+A(tv(t=f(t  (0≤t≤T,  v(0=v(λ+φ,  0<λ≤T in an arbitrary Banach space E with the dependent linear positive operator A(t is investigated. The well-posedness of this problem is established in Banach spaces C0β,γ(Eα-β of all Eα-β-valued continuous functions φ(t on [0,T] satisfying a Hölder condition with a weight (t+τγ. New Schauder type exact estimates in Hölder norms for the solution of two nonlocal boundary value problems for parabolic equations with dependent coefficients are established.

Safety significance of inadvertent operation of motor-operated valves in nuclear power plants

International Nuclear Information System (INIS)

Ruger, C.J.; Higgins, J.C.; Carbonaro, J.F.; Hall, R.E.

1994-01-01

Concerns about the consequences of valve mispositioning were brought to the forefront following an event at Davis Besse in 1985. The concern related to the ability to reposition open-quotes position-changeableclose quotes motor-operated valves (MOVs) from the control room in the event of their inadvertent operation and was documented in U.S. Nuclear Regulatory Commission (USNRC) Bulletin 85-03 and Generic Letter (GL) 89-10. The mispositioned MOVs may not be able to be returned to their required position due to high differential pressure or high flow conditions across the valves. The inability to reposition such valves may have significantly safety consequences, as in the Davis Besse event. However, full consideration of such mispositioning in safety analyses and in MOV test programs can be labor intensive and expensive. Industry raised concerns that consideration of position-changeable valves under GL 89-10 would not decrease the probability of core damage to an extent that would justify licensee costs. As a response, Brookhaven National Laboratory has conducted separate scoping studies for both boiling water reactors (BWRs) and pressurized water reactors (PWRs) using probabilistic risk assessment (PRA) techniques to determine if such valve mispositioning by itself is significant to safety. The approach used internal events PRA models to survey the order of magnitude of the risk-significance of valve mispositioning by considering the failure of selected position-changeable MOVs. The change in core damage frequency was determined for each valve considered, and the results were presented as a risk increase ratio for each of four assumed MOV failure rates. The risk increase ratios resulting from this failure rate sensitivity study can be used as a basis for a determination of the risk-significance of the MOV mispositioning issues for BWRs and PWRs

Spectral results for mixed problems and fractional elliptic operators,

DEFF Research Database (Denmark)

Grubb, Gerd

2015-01-01

In the first part of the paper we show Weyl type spectral asymptotic formulas for pseudodifferential operators P a of order 2a, with type and factorization index a  ∈ R +, restricted to compact sets with boundary; this includes fractional powers of the Laplace operator. The domain...... and the regularity of eigenfunctions is described. In the second part, we apply this in a study of realizations A χ,Σ+ in L 2( Ω ) of mixed problems for a second-order strongly elliptic symmetric differential operator A on a bounded smooth set Ω ⊂ R n; here the boundary ∂Ω=Σ is partioned smoothly into Σ......=Σ_∪Σ+, the Dirichlet condition γ0u=0 is imposed on Σ_, and a Neumann or Robin condition χu=0 is imposed on Σ+. It is shown that the Dirichlet-to-Neumann operator Pγ,χ is principally of type 1/2 with factorization index 1/2, relative to Σ+. The above theory allows a detailed description of D (Aχ,Σ_+) with singular...

Significance of post-operative changes of serum IL-18 levels in patients with renal transplantation

International Nuclear Information System (INIS)

Qi Falian; Xu Jun; Ke Bingshen; Du Xiumin; Yin Qiuxia; Hu Chengjin

2005-01-01

Objective: To study the clinical significance of post-operative changes of serum IL-18 levels in patients after renal transplantation. Methods: Serum IL-18 levels were detected with ELISA in 33 patients with renal transplantation before operation and repeated again on d5, d10 and d20 post-operatively as well as in 35 controls. Results: Pre-operatively, serum IL-18 levels in patients for upcoming renal transplantation were significantly higher than those in controls (P<0.01). After operation, the IL-18 levels on d5 and d10 in patients with acute rejection were not significantly changed from those pre-operatively but were markedly increased on d20 (vs pre-operative, d5, d10; all P<0.01). In the patients without rejection, levels in d5 were significantly higher than those pre-operatively, but dropped to approaching pre-operative values on d10 and d20. On d20, levels of serum IL-18 in patients with rejection were very significantly higher than those in stable patients (P<0.01). Conclusion: Serum IL-18 is a useful marker for identifying acute rejection. (authors)

Questioning the significance of the non-identity problem in applied ethics.

Science.gov (United States)

Lawlor, Rob

2015-11-01

Authors such as Tony Hope and Julian Savulescu appeal to Derek Parfit's non-identity problem in relation to particular questions in applied ethics, and particularly in reproductive ethics. They argue that the non-identity problem shows that an individual cannot be harmed by being brought into existence, and therefore, we cannot say that the individual is harmed if, for example, we select an embryo in order to have a deaf child. Thus, they argue that an appeal to the non-identity problem blocks (or significantly reduces the force of) objections in a number of cases. I argue that these discussions often give the impression that this is a clear conclusion, shared by most philosophers, and largely beyond dispute. This is particularly significant because these discussions are often in journals or books with an interdisciplinary readership. My concern is that they give the impression of stating: 'philosophers have studied this issue, and this is the conclusion they have reached. Now I will emphasise the implications for medical ethics'. I argue that, far from being the consensus view, the view presented by Hope and Savulescu is rejected by many, including Parfit himself. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Generalized ladder operators for the Dirac-Coulomb problem via SUSY QM

International Nuclear Information System (INIS)

Rodrigues, R. de Lima; Universidade Federal de Campina Grande, PB

2003-12-01

The supersymmetry in quantum mechanics and shape invariance condition are applied as an algebraic method to solving the Dirac-Coulomb problem. The ground state and the excited states are investigated via new generalized ladder operators. (author)

Some particular problems put by operating experimental reactors; Quelques problemes particuliers poses par le fonctionnement des piles laboratoires

Energy Technology Data Exchange (ETDEWEB)

Candiotti, C.; Mabeix, R.; Uguen, R. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

On basis of a six years experience in operating research reactors, the authors explain, first, the difference in their utilization between these piles and another similar ones and, after, in consequence, they set off corresponding servitudes. These servitudes put very particular problems in operating itself, maintenance, modifications or additions on these apparatus. (author) [French] Les redacteurs se basant sur six annees d'experience dans l'exploitation de reacteurs de recherche, exposent tout d'abord les differences d'utilisation entre ces engins et d'autres appareils fonctionnellement similaires et font ressortir, par voie de consequence, les servitudes correspondantes. Ces servitudes posent des problemes tres particuliers dans les domaines de l'exploitation proprement dite, de l'entretien, des modifications ou adjonctions apportees a l'ensemble. (auteur)

Cauchy problem for differential operators with double characteristics non-effectively hyperbolic characteristics

CERN Document Server

Nishitani, Tatsuo

2017-01-01

Combining geometrical and microlocal tools, this monograph gives detailed proofs of many well/ill-posed results related to the Cauchy problem for differential operators with non-effectively hyperbolic double characteristics. Previously scattered over numerous different publications, the results are presented from the viewpoint that the Hamilton map and the geometry of bicharacteristics completely characterizes the well/ill-posedness of the Cauchy problem. A doubly characteristic point of a differential operator P of order m (i.e. one where Pm = dPm = 0) is effectively hyperbolic if the Hamilton map FPm has real non-zero eigenvalues. When the characteristics are at most double and every double characteristic is effectively hyperbolic, the Cauchy problem for P can be solved for arbitrary lower order terms. If there is a non-effectively hyperbolic characteristic, solvability requires the subprincipal symbol of P to lie between − Pµj and P µj , where iµj are the positive imaginary eigenvalues of FPm ....

Evaluation of nuclear power plant operating procedures classifications and interfaces: Problems and techniques for improvement

International Nuclear Information System (INIS)

Barnes, V.E.; Radford, L.R.

1987-02-01

This report presents activities and findings of a project designed to evaluate current practices and problems related to procedure classification schemes and procedure interfaces in commercial nuclear power plants. The phrase ''procedure classification scheme'' refers to how plant operating procedures are categorized and indexed (e.g., normal, abnormal, emergency operating procedures). The term ''procedure interface'' refers to how reactor operators are instructed to transition within and between procedures. The project consisted of four key tasks, including (1) a survey of literature regarding problems associated with procedure classifications and interfaces, as well as techniques for overcoming them; (2) interviews with experts in the nuclear industry to discuss the appropriate scope of different classes of operating procedures and techniques for managing interfaces between them; (3) a reanalysis of data gathered about nuclear power plant normal operating and off-normal operating procedures in a related project, ''Program Plan for Assessing and Upgrading Operating Procedures for Nuclear Power Plants''; and (4) solicitation of the comments and expert opinions of a peer review group on the draft project report and on proposed techniques for resolving classification and interface issues. In addition to describing these activities and their results, recommendations for NRC and utility actions to address procedure classification and interface problems are offered

Learning to Solve Problems by Searching for Macro-Operators

Science.gov (United States)

1983-07-01

executing generalized robot plans. Aritificial Intelligence 3:25 1-288, 1972. [Frey 821 Frey, Alexander Ii. Jr., and David Singmaster. Handbook of Cubik...and that searching for macros may be a useful general learning paradigm. 1.1. Introduction One view of die die field of artificial intelligence is that... intelligence literature [Schofield 67, Gaschnig 79, Ericsson 761 and provides one of the simplest examples of the operation of the Macro Problem Solver. It

The operating room case-mix problem under uncertainty and nurses capacity constraints.

Science.gov (United States)

Yahia, Zakaria; Eltawil, Amr B; Harraz, Nermine A

2016-12-01

Surgery is one of the key functions in hospitals; it generates significant revenue and admissions to hospitals. In this paper we address the decision of choosing a case-mix for a surgery department. The objective of this study is to generate an optimal case-mix plan of surgery patients with uncertain surgery operations, which includes uncertainty in surgery durations, length of stay, surgery demand and the availability of nurses. In order to obtain an optimal case-mix plan, a stochastic optimization model is proposed and the sample average approximation method is applied. The proposed model is used to determine the number of surgery cases to be weekly served, the amount of operating rooms' time dedicated to each specialty and the number of ward beds dedicated to each specialty. The optimal case-mix selection criterion is based upon a weighted score taking into account both the waiting list and the historical demand of each patient category. The score aims to maximizing the service level of the operating rooms by increasing the total number of surgery cases that could be served. A computational experiment is presented to demonstrate the performance of the proposed method. The results show that the stochastic model solution outperforms the expected value problem solution. Additional analysis is conducted to study the effect of varying the number of ORs and nurses capacity on the overall ORs' performance.

Tax havens: Features, operations and solving tax evasion problems

OpenAIRE

Obradović-Ćuk, Jelena; Mitić, Petar; Dinić, Vladimir

2016-01-01

Tax haven offers minimal or no tax liability to foreign individuals and enterprises in economically and politically stable environment, where little or no financial information is shared with foreign tax authorities. The aim of this research is to create a comprehensive overview of the characteristics and operations of tax havens, as well as to point out to the ways to overcome the problem of tax evasion. The methodology used in the work is characteristic of social science research: analysis,...

A Riemann-Hilbert approach to the inverse problem for the Stark operator on the line

Science.gov (United States)

Its, A.; Sukhanov, V.

2016-05-01

The paper is concerned with the inverse scattering problem for the Stark operator on the line with a potential from the Schwartz class. In our study of the inverse problem, we use the Riemann-Hilbert formalism. This allows us to overcome the principal technical difficulties which arise in the more traditional approaches based on the Gel’fand-Levitan-Marchenko equations, and indeed solve the problem. We also produce a complete description of the relevant scattering data (which have not been obtained in the previous works on the Stark operator) and establish the bijection between the Schwartz class potentials and the scattering data.

Identification of Error Types in Preservice Teachers' Attempts to Create Fraction Story Problems for Specified Operations

Science.gov (United States)

McAllister, Cheryl J.; Beaver, Cheryl

2012-01-01

The purpose of this research was to determine if recognizable error types exist in the work of preservice teachers required to create story problems for specific fraction operations. Students were given a particular single-operation fraction expression and asked to do the calculation and then create a story problem that would require the use of…

A hybrid heuristic algorithm for the open-pit-mining operational planning problem.

OpenAIRE

Souza, Marcone Jamilson Freitas; Coelho, Igor Machado; Ribas, Sabir; Santos, Haroldo Gambini; Merschmann, Luiz Henrique de Campos

2010-01-01

This paper deals with the Open-Pit-Mining Operational Planning problem with dynamic truck allocation. The objective is to optimize mineral extraction in the mines by minimizing the number of mining trucks used to meet production goals and quality requirements. According to the literature, this problem is NPhard, so a heuristic strategy is justified. We present a hybrid algorithm that combines characteristics of two metaheuristics: Greedy Randomized Adaptive Search Procedures and General Varia...

Tax havens: Features, operations and solving tax evasion problems

Directory of Open Access Journals (Sweden)

Obradović-Ćuk Jelena

2016-01-01

Full Text Available Tax haven offers minimal or no tax liability to foreign individuals and enterprises in economically and politically stable environment, where little or no financial information is shared with foreign tax authorities. The aim of this research is to create a comprehensive overview of the characteristics and operations of tax havens, as well as to point out to the ways to overcome the problem of tax evasion. The methodology used in the work is characteristic of social science research: analysis, synthesis and discussion, comparative, inductive and historical analysis, together with the usage of relevant national and international sources. This paper describes the basic features of tax havens, as well as specific business models applied in them. A separate chapter deals with overcoming the problem of tax evasion, which is the main adverse effect of doing business through tax havens.

Operating experience feedback from safety significant events at research reactors

Energy Technology Data Exchange (ETDEWEB)

Shokr, A.M. [Atomic Energy Authority, Abouzabal (Egypt). Egypt Second Research Reactor; Rao, D. [Bhabha Atomic Research Centre, Mumbai (India)

2015-05-15

Operating experience feedback is an effective mechanism to provide lessons learned from the events and the associated corrective actions to prevent recurrence of events, resulting in improving safety in the nuclear installations. This paper analyzes the events of safety significance that have been occurred at research reactors and discusses the root causes and lessons learned from these events. Insights from literature on events at research reactors and feedback from events at nuclear power plants that are relevant to research reactors are also presented along with discussions. The results of the analysis showed the importance of communication of safety information and exchange of operating experience are vital to prevent reoccurrences of events. The analysis showed also the need for continued attention to human factors and training of operating personnel, and the need for establishing systematic ageing management programmes of reactor facilities, and programmes for safety management of handling of nuclear fuel, core components, and experimental devices.

Operating experience feedback from safety significant events at research reactors

International Nuclear Information System (INIS)

Shokr, A.M.

2015-01-01

Operating experience feedback is an effective mechanism to provide lessons learned from the events and the associated corrective actions to prevent recurrence of events, resulting in improving safety in the nuclear installations. This paper analyzes the events of safety significance that have been occurred at research reactors and discusses the root causes and lessons learned from these events. Insights from literature on events at research reactors and feedback from events at nuclear power plants that are relevant to research reactors are also presented along with discussions. The results of the analysis showed the importance of communication of safety information and exchange of operating experience are vital to prevent reoccurrences of events. The analysis showed also the need for continued attention to human factors and training of operating personnel, and the need for establishing systematic ageing management programmes of reactor facilities, and programmes for safety management of handling of nuclear fuel, core components, and experimental devices.

On the convex closed set-valued operators in Banach spaces and their applications in control problems

International Nuclear Information System (INIS)

Vu Ngoc Phat; Jong Yeoul Park

1995-10-01

The paper studies a class of set-values operators with emphasis on properties of their adjoints and existence of eigenvalues and eigenvectors of infinite-dimensional convex closed set-valued operators. Sufficient conditions for existence of eigenvalues and eigenvectors of set-valued convex closed operators are derived. These conditions specify possible features of control problems. The results are applied to some constrained control problems of infinite-dimensional systems described by discrete-time inclusions whose right-hand-sides are convex closed set- valued functions. (author). 8 refs

Significance of Operating Environment in Condition Monitoring of Large Civil Structures

OpenAIRE

Alampalli, Sreenivas

1999-01-01

Success of remote long-term condition monitoring of large civil structures and developing calibrated analytical models for damage detection, depend significantly on establishing accurate baseline signatures and their sensitivity. Most studies reported in the literature concentrated on the effect of structural damage on modal parameters without emphasis on reliability of modal parameters. Thus, a field bridge structure was studied for the significance of operating conditions in relation to bas...

Clinically Significant Behavior Problems among Young Children 2 Years after the Great East Japan Earthquake

Science.gov (United States)

Fujiwara, Takeo; Yagi, Junko; Homma, Hiroaki; Mashiko, Hirobumi; Nagao, Keizo; Okuyama, Makiko

2014-01-01

Background On March 11, 2011, a massive undersea earthquake and tsunami struck East Japan. Few studies have investigated the impact of exposure to a natural disaster on preschool children. We investigated the association of trauma experiences during the Great East Japan Earthquake on clinically significant behavior problems among preschool children 2 years after the earthquake. Method Participants were children who were exposed to the 2011 disaster at preschool age (affected area, n = 178; unaffected area, n = 82). Data were collected from September 2012 to June 2013 (around 2 years after the earthquake), thus participants were aged 5 to 8 years when assessed. Severe trauma exposures related to the earthquake (e.g., loss of family members) were assessed by interview, and trauma events in the physical environment related to the earthquake (e.g. housing damage), and other trauma exposure before the earthquake, were assessed by questionnaire. Behavior problems were assessed by caregivers using the Child Behavior Checklist (CBCL), which encompasses internalizing, externalizing, and total problems. Children who exceeded clinical cut-off of the CBCL were defined as having clinically significant behavior problems. Results Rates of internalizing, externalizing, and total problems in the affected area were 27.7%, 21.2%, and 25.9%, respectively. The rate ratio suggests that children who lost distant relatives or friends were 2.36 times more likely to have internalizing behavior problems (47.6% vs. 20.2%, 95% CI: 1.10–5.07). Other trauma experiences before the earthquake also showed significant positive association with internalizing, externalizing, and total behavior problems, which were not observed in the unaffected area. Conclusions One in four children still had behavior problems even 2 years after the Great East Japan Earthquake. Children who had other trauma experiences before the earthquake were more likely to have behavior problems. These data will be

Application of the annihilation and creation operators in magnetic resonance problems

International Nuclear Information System (INIS)

Nosel, W.

1981-01-01

Application of the annihilation and creation operators in the following problems is presented: in the resonance of the free spins in rotating and oscillating magnetic field, in the influence of the nonresonance magnetic fields on magnetic resonance, in the thermodynamics of the spins with dipolar interaction and in the nuclear magnetic relaxation. (author)

Concerned significant others of people with gambling problems in Finland: a cross-sectional population study.

Science.gov (United States)

Salonen, Anne H; Castrén, Sari; Alho, Hannu; Lahti, Tuuli

2014-04-24

Problem gambling not only impacts those directly involved, but also the concerned significant others (CSOs) of problem gamblers. The aims of this study were to investigate the proportion of male and female CSOs at the population level; to investigate who the CSOs were concerned about; and to investigate sociodemographic factors, gender differences, gambling behaviour, and health and well-being among CSOs and non-CSOs. The data (n = 4484) were based on a cross-sectional population study. Structured telephone interviews were conducted in 2011-2012. The data were weighted based on age, gender and residency. The respondents were defined as CSOs if they reported that at least one of their significant others (father, mother, sister/brother, grandparent, spouse, own child/children, close friend) had had gambling problems. Statistical significance was determined by chi-squared and Fisher's exact tests, and logistic regression analysis. Altogether, 19.3% of the respondents were identified as CSOs. Most commonly, the problem gambler was a close friend (12.4%) of the CSO. The percentage of close friends having a gambling problem was larger among male CSOs (14.4%) compared with female CSOs (10.3%; p ≤ 0.001), while the percentage of partners with gambling problem was larger among females (2.6%) than among males (0.8%; p ≤ 0.001). In the best fitting model, the odds ratio (95% CI) of being a male CSO was 2.03 (1.24-3.31) for past-year gambling problems, 1.46 (1.08-1.97) for loneliness and 1.78 (1.38-2.29) for risky alcohol consumption. The odds ratio (95% CI) of being a female CSO was 1.51 (1.09-2.08) for past-year gambling involvement, 3.05 (1.18-7.90) for past-year gambling problems, 2.21 (1.24-3.93) for mental health problems, 1.39 (1.03-1.89) for loneliness and 1.97 (1.43-2.71) for daily smoking. CSOs of problem gamblers often experience cumulating problems such as their own risky gambling behaviour, health problems and other addictive disorders. The

Vertex operators, non-abelian orbifolds and the Riemann-Hilbert problem

International Nuclear Information System (INIS)

Gato, B.; Massachusetts Inst. of Tech., Cambridge

1990-01-01

We show how to construct the oscillator part of vertex operators for the bosonic string moving on non-abelian orbifolds, using the conserved charges method. When the three-string vertices are twisted by non-commuting group elements, the construction of the conserved charges becomes the Riemann-Hilbert problem with monodromy matrices given by the twists. This is solvable for any given configuration and any non-abelian orbifold. (orig.)

Robustness of Operational Matrices of Differentiation for Solving State-Space Analysis and Optimal Control Problems

Directory of Open Access Journals (Sweden)

Emran Tohidi

2013-01-01

Full Text Available The idea of approximation by monomials together with the collocation technique over a uniform mesh for solving state-space analysis and optimal control problems (OCPs has been proposed in this paper. After imposing the Pontryagins maximum principle to the main OCPs, the problems reduce to a linear or nonlinear boundary value problem. In the linear case we propose a monomial collocation matrix approach, while in the nonlinear case, the general collocation method has been applied. We also show the efficiency of the operational matrices of differentiation with respect to the operational matrices of integration in our numerical examples. These matrices of integration are related to the Bessel, Walsh, Triangular, Laguerre, and Hermite functions.

Problems affecting the operational procurement process: A study of the Zimbabwean public sector

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Abel Dzuke

2017-02-01

Full Text Available Background: The public sector occupies a key role in the economy comprising the appropriation of state revenue to purchase goods and to render services productively, while ensuring the optimum utilisation of available funds and resources to benefit the inhabitants of the country. Problems in the Zimbabwean public procurement sector that detract from service delivery are key contemporary issues. This is evident from the numerous complaints of poor service delivery received by the public that can be attributed to public procurement. Objective: The purpose of this article was to report on a study that investigated problems in the different stages of the operational procurement process in the Zimbabwean public sector that detract from service delivery, the extent of these problems and how the public procurement process can be improved to enhance service delivery. Method: This descriptive and exploratory study followed a quantitative approach. Data were collected by means of a questionnaire administered to all public entities in Zimbabwe. Data were analysed using SPSS. Results: The majority of the identified problems in the public procurement sector that detract from service delivery are found in the advertising, bid evaluation and contract stages. Conclusion: As only a few studies on this topic have been conducted in Zimbabwe, the findings of this research add a significant perspective to the existing body of knowledge and can assist stakeholders with regard to how the public procurement process can be improved in order to enhance service delivery through public procurement process reform and restructuring.

Triple solutions for multi-point boundary-value problem with p-Laplace operator

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Yansheng Liu

2009-11-01

Full Text Available Using a fixed point theorem due to Avery and Peterson, this article shows the existence of solutions for multi-point boundary-value problem with p-Laplace operator and parameters. Also, we present an example to illustrate the results obtained.

Solving the multiple-set split equality common fixed-point problem of firmly quasi-nonexpansive operators.

Science.gov (United States)

Zhao, Jing; Zong, Haili

2018-01-01

In this paper, we propose parallel and cyclic iterative algorithms for solving the multiple-set split equality common fixed-point problem of firmly quasi-nonexpansive operators. We also combine the process of cyclic and parallel iterative methods and propose two mixed iterative algorithms. Our several algorithms do not need any prior information about the operator norms. Under mild assumptions, we prove weak convergence of the proposed iterative sequences in Hilbert spaces. As applications, we obtain several iterative algorithms to solve the multiple-set split equality problem.

The corona problem connections between operator theory, function theory, and geometry

CERN Document Server

Krantz, Steven; Sawyer, Eric; Treil, Sergei; Wick, Brett

2014-01-01

The purpose of the corona workshop was to consider the corona problem in both one and several complex variables, both in the context of function theory and harmonic analysis as well as the context of operator theory and functional analysis. It was held in June 2012 at the Fields Institute in Toronto, and attended by about fifty mathematicians. This volume validates and commemorates the workshop, and records some of the ideas that were developed within. The corona problem dates back to 1941. It has exerted a powerful influence over mathematical analysis for nearly 75 years. There is material to help bring people up to speed in the latest ideas of the subject, as well as historical material to provide background. Particularly noteworthy is a history of the corona problem, authored by the five organizers, that provides a unique glimpse at how the problem and its many different solutions have developed. There has never been a meeting of this kind, and there has never been a volume of this kind. Mathematicians—...

Electromagnetic Problems Solving by Conformal Mapping: A Mathematical Operator for Optimization

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Wesley Pacheco Calixto

2010-01-01

Full Text Available Having the property to modify only the geometry of a polygonal structure, preserving its physical magnitudes, the Conformal Mapping is an exceptional tool to solve electromagnetism problems with known boundary conditions. This work aims to introduce a new developed mathematical operator, based on polynomial extrapolation. This operator has the capacity to accelerate an optimization method applied in conformal mappings, to determinate the equipotential lines, the field lines, the capacitance, and the permeance of some polygonal geometry electrical devices with an inner dielectric of permittivity ε. The results obtained in this work are compared with other simulations performed by the software of finite elements method, Flux 2D.

A split operator method for transient problems

International Nuclear Information System (INIS)

Belytschko, T.B.

1983-01-01

Numerous techniques have been developed for improving the computational efficiency of transient analysis: mesh partitioning, subcycling procedures and operator splitting methods. In mesh partitioning methods, the model is divided into subdomains which are integrated by different time integrators, typically implicit and explicit. Any stiff portions of the model are integrated by the implicit operator so that the size of the time step can be increased. In subcycling procedures, the stiff portions are integrated by smaller time steps, yielding similar benefits. However, in models for which the governing partial differential equations are basically of a parabolic character, explicit methods can become quite expensive for refined models because the size of the stable time step decreases with the square of the minimum element dimension. Thus explicit methods, whether employed alone or with partitioning or subcycling, have inherent limitations in these problems. A new procedure is here described for the element-by-element semi-implicit method of Hughes and coworkers which requires the solution of only small systems of equations. This procedure is described for a family of uniform gradient or strain elements which are widely used in nonlinear transient analysis. The diffusion equation and the equations of motion for both shells and continua have been treated, but only the former is considered herein. Results are presented for several examples which show the potential of this method for improving the efficiency of a large-scale linear and nonlinear computations. (orig./RW)

Types of Motivating Operations in Interventions with Problem Behavior: A Systematic Review

Science.gov (United States)

Simo-Pinatella, David; Font-Roura, Josep; Planella-Morato, Joaquima; McGill, Peter; Alomar-Kurz, Elisabeth; Gine, Climent

2013-01-01

A motivating operation (MO) alters both the effectiveness of a stimulus as a reinforcer and the current frequency of all behavior that has been reinforced by that particular stimulus. This article reviews studies that have manipulated a MO during interventions with school-age participants with intellectual disabilities and problem behavior. A…

Indistinguishability Operators Applied to Task Allocation Problems in Multi-Agent Systems

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José Guerrero

2017-09-01

Full Text Available In this paper we show an application of indistinguishability operators to model response functions. Such functions are used in the mathematical modeling of the task allocation problem in multi-agent systems when the stimulus, perceived by the agent, to perform a task is assessed by means of the response threshold model. In particular, we propose this kind of operators to represent a response function when the stimulus only depends on the distance between the agent and a determined task, since we prove that two celebrated response functions used in the literature can be reproduced by appropriate indistinguishability operators when the stimulus only depends on the distance to each task that must be carried out. Despite the fact there is currently no systematic method to generate response functions, this paper provides, for the first time, a theoretical foundation to generate them and study their properties. To validate the theoretical results, the aforementioned indistinguishability operators have been used to simulate, with MATLAB, the allocation of a set of tasks in a multi-robot system with fuzzy Markov chains.

Hybrid Proximal-Point Methods for Zeros of Maximal Monotone Operators, Variational Inequalities and Mixed Equilibrium Problems

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Kriengsak Wattanawitoon

2011-01-01

Full Text Available We prove strong and weak convergence theorems of modified hybrid proximal-point algorithms for finding a common element of the zero point of a maximal monotone operator, the set of solutions of equilibrium problems, and the set of solution of the variational inequality operators of an inverse strongly monotone in a Banach space under different conditions. Moreover, applications to complementarity problems are given. Our results modify and improve the recently announced ones by Li and Song (2008 and many authors.

Solution of operational problems utilization of an EX-IRT-2000 heat exchanger

International Nuclear Information System (INIS)

Razak, Abdu

1986-01-01

The Bandung TRIGA Mark II Reactor has been successfully operated for 21 years, especially in low power operation or as neutron sources for various experiments. Most of the operating time, approximately 80% of routine operation, was dedicated for radio-isotope production. During routine operation for radio-isotope production, the reactor could not be operated at full power. The reactor was operated at 60% of the maximum power (1 MWth) due to the inability of the original heat exchanger to operate properly. The reason is that slack deposition was built-up on the secondary side of the heat exchanger. Therefore, it reduced the coefficient of heat transfer considerably. To solve the problems, a set of heat exchanger including the pump was installed In parallel with the original unit. The heat exchanger was an IRT-2000 Reactor Heat exchanger which was collected from the abandoned IRT-2000 Project. The heat exchanger has capacity of 1.25 MW. The new heat exchanger could reduced the outlet temperature of the primary coolant Into 42 deg. C. While the original-heat exchanger at the worst condition and at 600 kW of power reach outlet temperature 49 deg. C. The IRT Heat Exchanger is a counter flow heat exchanger. (author)

Solution of operational problems utilization of an EX-IRT-2000 heat exchanger

Energy Technology Data Exchange (ETDEWEB)

Razak, Abdu [Research Centre for Nuclear Techniques, National Atomic Energy Agency (Indonesia)

1986-07-01

The Bandung TRIGA Mark II Reactor has been successfully operated for 21 years, especially in low power operation or as neutron sources for various experiments. Most of the operating time, approximately 80% of routine operation, was dedicated for radio-isotope production. During routine operation for radio-isotope production, the reactor could not be operated at full power. The reactor was operated at 60% of the maximum power (1 MWth) due to the inability of the original heat exchanger to operate properly. The reason is that slack deposition was built-up on the secondary side of the heat exchanger. Therefore, it reduced the coefficient of heat transfer considerably. To solve the problems, a set of heat exchanger including the pump was installed In parallel with the original unit. The heat exchanger was an IRT-2000 Reactor Heat exchanger which was collected from the abandoned IRT-2000 Project. The heat exchanger has capacity of 1.25 MW. The new heat exchanger could reduced the outlet temperature of the primary coolant Into 42 deg. C. While the original-heat exchanger at the worst condition and at 600 kW of power reach outlet temperature 49 deg. C. The IRT Heat Exchanger is a counter flow heat exchanger. (author)

Solving optimum operation of single pump unit problem with ant colony optimization (ACO) algorithm

International Nuclear Information System (INIS)

Yuan, Y; Liu, C

2012-01-01

For pumping stations, the effective scheduling of daily pump operations from solutions to the optimum design operation problem is one of the greatest potential areas for energy cost-savings, there are some difficulties in solving this problem with traditional optimization methods due to the multimodality of the solution region. In this case, an ACO model for optimum operation of pumping unit is proposed and the solution method by ants searching is presented by rationally setting the object function and constrained conditions. A weighted directed graph was constructed and feasible solutions may be found by iteratively searching of artificial ants, and then the optimal solution can be obtained by applying the rule of state transition and the pheromone updating. An example calculation was conducted and the minimum cost was found as 4.9979. The result of ant colony algorithm was compared with the result from dynamic programming or evolutionary solving method in commercial software under the same discrete condition. The result of ACO is better and the computing time is shorter which indicates that ACO algorithm can provide a high application value to the field of optimal operation of pumping stations and related fields.

Safety management in multiemployer worksites in the manufacturing industry: opinions on co-operation and problems encountered.

Science.gov (United States)

Nenonen, Sanna; Vasara, Juha

2013-01-01

Co-operation between different parties and effective safety management play an important role in ensuring safety in multiemployer worksites. This article reviews safety co-operation and factors complicating safety management in Finnish multiemployer manufacturing worksites. The paper focuses on the service providers' opinions; however, a comparison of the customers' views is also presented. The results show that safety-related co-operation between providers and customers is generally considered as successful but strongly dependent on the partner. Safety co-operation is provided through, e.g., training, orientation and risk analysis. Problems encountered include ensuring adequate communication, identifying hazards, co-ordinating work tasks and determining responsibilities. The providers and the customers encounter similar safety management problems. The results presented in this article can help companies to focus their efforts on the most problematic points of safety management and to avoid common pitfalls.

On Lambda and Time Operators: the Inverse Intertwining Problem Revisited

Science.gov (United States)

Gómez-Cubillo, F.; Suchanecki, Z.; Villullas, S.

2011-07-01

An exact theory of irreversibility was proposed by Misra, Prigogine and Courbage, based on non-unitary similarity transformations Λ that intertwine reversible dynamics and irreversible ones. This would advocate the idea that irreversible behavior would originate at the microscopic level. Reversible evolution with an internal time operator have the intertwining property. Recently the inverse intertwining problem has been answered in the negative, that is, not every unitary evolution allowing such Λ-transformation has an internal time. This work contributes new results in this direction.

Risk-Based Two-Stage Stochastic Optimization Problem of Micro-Grid Operation with Renewables and Incentive-Based Demand Response Programs

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Pouria Sheikhahmadi

2018-03-01

Full Text Available The operation problem of a micro-grid (MG in grid-connected mode is an optimization one in which the main objective of the MG operator (MGO is to minimize the operation cost with optimal scheduling of resources and optimal trading energy with the main grid. The MGO can use incentive-based demand response programs (DRPs to pay an incentive to the consumers to change their demands in the peak hours. Moreover, the MGO forecasts the output power of renewable energy resources (RERs and models their uncertainties in its problem. In this paper, the operation problem of an MGO is modeled as a risk-based two-stage stochastic optimization problem. To model the uncertainties of RERs, two-stage stochastic programming is considered and conditional value at risk (CVaR index is used to manage the MGO’s risk-level. Moreover, the non-linear economic models of incentive-based DRPs are used by the MGO to change the peak load. The numerical studies are done to investigate the effect of incentive-based DRPs on the operation problem of the MGO. Moreover, to show the effect of the risk-averse parameter on MGO decisions, a sensitivity analysis is carried out.

Layer potentials and boundary-value problems for second order elliptic operators with data in Besov spaces

CERN Document Server

Barton, Ariel

2016-01-01

This monograph presents a comprehensive treatment of second order divergence form elliptic operators with bounded measurable t-independent coefficients in spaces of fractional smoothness, in Besov and weighted L^p classes. The authors establish: (1) Mapping properties for the double and single layer potentials, as well as the Newton potential; (2) Extrapolation-type solvability results: the fact that solvability of the Dirichlet or Neumann boundary value problem at any given L^p space automatically assures their solvability in an extended range of Besov spaces; (3) Well-posedness for the non-homogeneous boundary value problems. In particular, the authors prove well-posedness of the non-homogeneous Dirichlet problem with data in Besov spaces for operators with real, not necessarily symmetric, coefficients.

A Hybrid Genetic Algorithm with a Knowledge-Based Operator for Solving the Job Shop Scheduling Problems

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Hamed Piroozfard

2016-01-01

Full Text Available Scheduling is considered as an important topic in production management and combinatorial optimization in which it ubiquitously exists in most of the real-world applications. The attempts of finding optimal or near optimal solutions for the job shop scheduling problems are deemed important, because they are characterized as highly complex and NP-hard problems. This paper describes the development of a hybrid genetic algorithm for solving the nonpreemptive job shop scheduling problems with the objective of minimizing makespan. In order to solve the presented problem more effectively, an operation-based representation was used to enable the construction of feasible schedules. In addition, a new knowledge-based operator was designed based on the problem’s characteristics in order to use machines’ idle times to improve the solution quality, and it was developed in the context of function evaluation. A machine based precedence preserving order-based crossover was proposed to generate the offspring. Furthermore, a simulated annealing based neighborhood search technique was used to improve the local exploitation ability of the algorithm and to increase its population diversity. In order to prove the efficiency and effectiveness of the proposed algorithm, numerous benchmarked instances were collected from the Operations Research Library. Computational results of the proposed hybrid genetic algorithm demonstrate its effectiveness.

Process pump operating problems and equipment failures, F-Canyon Reprocessing Facility, Savannah River Plant

International Nuclear Information System (INIS)

Durant, W.S.; Starks, J.B.; Galloway, W.D.

1987-02-01

A compilation of operating problems and equipment failures associated with the process pumps in the Savannah River Plant F-Canyon Fuel Reprocessing Facility is presented. These data have been collected over the 30-year operation of the facility. An analysis of the failure rates of the pumps is also presented. A brief description of the pumps and the data bank from which the information was sorted is also included

ABOLISHING AND ESTABLISHING OPERATION ANALYSES OF SOCIAL ATTENTION AS POSITIVE REINFORCEMENT FOR PROBLEM BEHAVIOR

OpenAIRE

McGinnis, Molly A; Houchins-Juárez, Nealetta; McDaniel, Jill L; Kennedy, Craig H

2010-01-01

Three participants whose problem behavior was maintained by contingent attention were exposed to 45-min presessions in which attention was withheld, provided on a fixed-time (FT) 15-s schedule, or provided on an FT 120-s schedule. Following each presession, participants were then tested in a 15-min session similar to the social attention condition of an analogue functional analysis. The results showed establishing operation conditions increased problem behavior during tests and that abolishin...

A new operational approach for solving fractional variational problems depending on indefinite integrals

Science.gov (United States)

Ezz-Eldien, S. S.; Doha, E. H.; Bhrawy, A. H.; El-Kalaawy, A. A.; Machado, J. A. T.

2018-04-01

In this paper, we propose a new accurate and robust numerical technique to approximate the solutions of fractional variational problems (FVPs) depending on indefinite integrals with a type of fixed Riemann-Liouville fractional integral. The proposed technique is based on the shifted Chebyshev polynomials as basis functions for the fractional integral operational matrix (FIOM). Together with the Lagrange multiplier method, these problems are then reduced to a system of algebraic equations, which greatly simplifies the solution process. Numerical examples are carried out to confirm the accuracy, efficiency and applicability of the proposed algorithm

Oxygen sensor equipped engine operation on methanol/gasoline blends and phase separation problems

Energy Technology Data Exchange (ETDEWEB)

Last, A J; Lawson, A; Simmons, E W; Mackay, D; Tsang, M; Maund, G B

1980-01-01

A study was made to address problems related to Canadian utilization of methanol/gasoline blends. These problems are: (1) cold weather operation; (2) water sensitivity to phase separation in winter; (3) vehicle compatibility: fuel/air ratio control, flexibility for vehicle movement outside of areas where methanol might be available. Specifically, the operation of the HydroShear (an in-line hydraulic emulsifier) on the two separated phases of a methanol/gasoline/water blend was examined. Fuel maps, by engine dynamometer testing, were generated using methanol/gasoline blends containing 15% to 65% methanol. The capability of an oxygen sensor, located in the exhaust system, to control the fuel/air ratio was found to be adequate within the 15% to 65% methanol/gasoline blends. A fuel injected Volvo 244DL with lambda-sond emission control and a carburetted Chevrolet Monza with 3-way catalyst closed loop feedback emission control system were the two engines selected for this study.

Significance of Operating Environment in Condition Monitoring of Large Civil Structures

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Sreenivas Alampalli

1999-01-01

Full Text Available Success of remote long-term condition monitoring of large civil structures and developing calibrated analytical models for damage detection, depend significantly on establishing accurate baseline signatures and their sensitivity. Most studies reported in the literature concentrated on the effect of structural damage on modal parameters without emphasis on reliability of modal parameters. Thus, a field bridge structure was studied for the significance of operating conditions in relation to baseline signatures. Results indicate that in practice, civil structures should be monitored for at least one full cycle of in-service environmental changes before establishing baselines for condition monitoring or calibrating finite-element models. Boundary conditions deserve special attention.

Analysis of the State of Operation Management at Industrial Enterprises

OpenAIRE

Zakharov Vladimir A.; Ivanova Valentina I.

2013-01-01

The article analyses operation management at industrial enterprises of the Kharkiv region, identifies main problems and offers ways of improvement of the quality of operation management at industrial enterprises of Ukraine. It marks out the factors of the competitive environment of the operation system, which exert significant influence on operation management of an industrial enterprise. It builds a diagram of problems and a tree of goals of elimination of problems of operation management.Пр...

Study on the man-operator characteristics in the peak identification problem in line spectra

International Nuclear Information System (INIS)

Gopych, P.M.; Sorokin, V.I.; Sotnikov, V.V.

1992-01-01

ATOS program complex (automatical test spectra processing) realizing all stages of investigation necessary to obtain qualitative characteristics of the man-operator in the peak identification problem is developed. Qualitative characteristics of identitication ion quality of peaks by operators searching for peaks in line spectra are determined due to simulation experiment. It is shown, that for trained operators reference possibility of false detection of peaks is equal to F=0.012±0.004, while for untrained ones - F≅0.3. Comparison of results with analogous data on on-line programs for identification of peaks in γ-spectra is conducted

The nonlocal problem for a hyperbolic equation with Bessel operator in a rectangular domain

Directory of Open Access Journals (Sweden)

Natalya V. Zaitseva

2016-12-01

Full Text Available We consider a boundary value problem for a hyperbolic equation with Bessel differential operator in a rectangular domain with integral nonlocal boundary value condition of the first kind. The equivalence between boundary value problem with integral nonlocal condition of the first kind and a local boundary value problem with mixed boundary conditions of the first and third kinds is proved. The existence and uniqueness of solution of the equivalent problem are established by means of the spectral method. At the uniqueness proof the completeness of the eigenfunction system of the spectral problem is used . At the existence proof the assessment of coefficients of series, the asymptotic formula for Bessel function of the first kind and asymptotic formula for eigenvalues are used. Sufficient conditions on the functions defining initial data of the problem are received. The solution of the problem is obtained in explicit form. The solution is obtained in the form of the Fourier–Bessel series. Its convergence is proved in the class of regular solutions.

Harmonic voltage excess problem test and analysis in UHV and EHV grid particular operation mode

Science.gov (United States)

Lv, Zhenhua; Shi, Mingming; Fei, Juntao

2018-02-01

The test and analysis of the power quality of some 1000kV UHV transmission lines and 500kV EHV transmission lines is carried out. It is found that there is harmonic voltage excess problems when the power supply of the UHV and EHV voltage line is single-ended or single-loop, the problem basically disappeared after the operation mode change, different operating conditions, the harmonic current has not been greatly affected, indicating that the harmonic voltage changes mainly caused by the system harmonic impedance. With the analysis of MATLAB Simulink system model, it can be seen that there are specific harmonic voltage excess in the system under the specific operating mode, which results in serious distortion of the specific harmonic voltage. Since such phenomena are found in 500kV and 1000kV systems, it is suggested that the test evaluation work should be done under the typical mode of operation in 500kV, 1000kV Planning and construction process to prevent the occurrence of serious distortion and the regional harmonic current monitoring and suppression work should be done.

Problems with numerical techniques: Application to mid-loop operation transients

Energy Technology Data Exchange (ETDEWEB)

Bryce, W.M.; Lillington, J.N.

1997-07-01

There has been an increasing need to consider accidents at shutdown which have been shown in some PSAs to provide a significant contribution to overall risk. In the UK experience has been gained at three levels: (1) Assessment of codes against experiments; (2) Plant studies specifically for Sizewell B; and (3) Detailed review of modelling to support the plant studies for Sizewell B. The work has largely been carried out using various versions of RELAP5 and SCDAP/RELAP5. The paper details some of the problems that have needed to be addressed. It is believed by the authors that these kinds of problems are probably generic to most of the present generation system thermal-hydraulic codes for the conditions present in mid-loop transients. Thus as far as possible these problems and solutions are proposed in generic terms. The areas addressed include: condensables at low pressure, poor time step calculation detection, water packing, inadequate physical modelling, numerical heat transfer and mass errors. In general single code modifications have been proposed to solve the problems. These have been very much concerned with means of improving existing models rather than by formulating a completely new approach. They have been produced after a particular problem has arisen. Thus, and this has been borne out in practice, the danger is that when new transients are attempted, new problems arise which then also require patching.

Measures for simultaneous minimisation of alkali related operating problems; Aatgaerder foer samtidig minimering av alkalirelaterade driftproblem. Ramprogram

Energy Technology Data Exchange (ETDEWEB)

Davidsson, Kent; Eskilsson, David; Gyllenhammar, Marianne; Herstad Svaerd, Solvie; Kassman, Haakan; Steenari, Britt-Marie; Aamand, Lars-Erik

2006-12-15

Combustion of biofuel and waste wood is often accompanied by chlorine and alkali related operating problems such as slagging, deposit formation and corrosion on heat exchanger surfaces and bed agglomeration in fluidised bed boilers. In order to gain a greater insight into possible measures to overcome alkali related operating problems studies were carried out during 2005-2006. The results of the studies are presented in this report which includes work performed in the two following projects: 1 A5-509 Frame work - measures for simultaneous minimisation of alkali related operating problems 2 A5-505 Bed agglomeration risk related to combustion of cultivated fuels (wheat straw, red canary grass, industrial hemp) in commercial bed materials Full-scale experiments were carried out at Chalmers 12 MW{sub th} CFB boiler within the project A5-509. The purpose was to study the effect of various measures on bed agglomeration and deposit formation in connection with co-combustion of wood and straw pellets. The various measures included changing the bed material (blast furnace sand and olivine sand), adding various additives (kaolin, ammonium sulphate, elemental sulphur) and also co-combustion with sewage sludge. Furthermore results from kaolin experiments at the 26 MWth CFB boiler owned by Naessjoe Affaersverk were made available during the project and are also presented in this report. The results from the experiments at Chalmers revealed that, already at the lowest dosage of kaolin, approx. 2 kg/MWh, the bed material agglomeration temperatures increased significantly. The dosage of kaolin can presumably be reduced somewhat further while still maintaining the high agglomeration temperature. Experiments with a higher dosage of kaolin, 7 kg/MWh, proved that kaolin could also reduce the risk of deposit problems. The experiments at Naessjoe showed also that addition of kaolin increased the agglomeration temperature of the bed material. Addition of sulphur in any form resulted in a

Cauchy problem for a parabolic equation with Bessel operator and Riemann–Liouville partial derivative

Directory of Open Access Journals (Sweden)

Fatima G. Khushtova

2016-03-01

Full Text Available In this paper Cauchy problem for a parabolic equation with Bessel operator and with Riemann–Liouville partial derivative is considered. The representation of the solution is obtained in terms of integral transform with Wright function in the kernel. It is shown that when this equation becomes the fractional diffusion equation, obtained solution becomes the solution of Cauchy problem for the corresponding equation. The uniqueness of the solution in the class of functions that satisfy the analogue of Tikhonov condition is proved.

Algorithm for complete enumeration based on a stroke graph to solve the supply network configuration and operations scheduling problem

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Julien Maheut

2013-07-01

Full Text Available Purpose: The purpose of this paper is to present an algorithm that solves the supply network configuration and operations scheduling problem in a mass customization company that faces alternative operations for one specific tool machine order in a multiplant context. Design/methodology/approach: To achieve this objective, the supply chain network configuration and operations scheduling problem is presented. A model based on stroke graphs allows the design of an algorithm that enumerates all the feasible solutions. The algorithm considers the arrival of a new customized order proposal which has to be inserted into a scheduled program. A selection function is then used to choose the solutions to be simulated in a specific simulation tool implemented in a Decision Support System. Findings and Originality/value: The algorithm itself proves efficient to find all feasible solutions when alternative operations must be considered. The stroke structure is successfully used to schedule operations when considering more than one manufacturing and supply option in each step. Research limitations/implications: This paper includes only the algorithm structure for a one-by-one, sequenced introduction of new products into the list of units to be manufactured. Therefore, the lotsizing process is done on a lot-per-lot basis. Moreover, the validation analysis is done through a case study and no generalization can be done without risk. Practical implications: The result of this research would help stakeholders to determine all the feasible and practical solutions for their problem. It would also allow to assessing the total costs and delivery times of each solution. Moreover, the Decision Support System proves useful to assess alternative solutions. Originality/value: This research offers a simple algorithm that helps solve the supply network configuration problem and, simultaneously, the scheduling problem by considering alternative operations. The proposed system

A classical Perron method for existence of smooth solutions to boundary value and obstacle problems for degenerate-elliptic operators via holomorphic maps

Science.gov (United States)

Feehan, Paul M. N.

2017-09-01

We prove existence of solutions to boundary value problems and obstacle problems for degenerate-elliptic, linear, second-order partial differential operators with partial Dirichlet boundary conditions using a new version of the Perron method. The elliptic operators considered have a degeneracy along a portion of the domain boundary which is similar to the degeneracy of a model linear operator identified by Daskalopoulos and Hamilton [9] in their study of the porous medium equation or the degeneracy of the Heston operator [21] in mathematical finance. Existence of a solution to the partial Dirichlet problem on a half-ball, where the operator becomes degenerate on the flat boundary and a Dirichlet condition is only imposed on the spherical boundary, provides the key additional ingredient required for our Perron method. Surprisingly, proving existence of a solution to this partial Dirichlet problem with ;mixed; boundary conditions on a half-ball is more challenging than one might expect. Due to the difficulty in developing a global Schauder estimate and due to compatibility conditions arising where the ;degenerate; and ;non-degenerate boundaries; touch, one cannot directly apply the continuity or approximate solution methods. However, in dimension two, there is a holomorphic map from the half-disk onto the infinite strip in the complex plane and one can extend this definition to higher dimensions to give a diffeomorphism from the half-ball onto the infinite ;slab;. The solution to the partial Dirichlet problem on the half-ball can thus be converted to a partial Dirichlet problem on the slab, albeit for an operator which now has exponentially growing coefficients. The required Schauder regularity theory and existence of a solution to the partial Dirichlet problem on the slab can nevertheless be obtained using previous work of the author and C. Pop [16]. Our Perron method relies on weak and strong maximum principles for degenerate-elliptic operators, concepts of

Significance of operator variation and the angle of illumination in lineament analysis on synoptic images. [LANDSAT geological investigations

Science.gov (United States)

Siegal, B. S.; Short, N. M.

1977-01-01

The significance of operator variation and the angle of illumination in acquired imagery is analyzed for lineament analysis. Five operators analyzed a LANDSAT image and four photographs of a plastic relief map illuminated at a low angle from varying directions of the Prescott, Arizona region. Significant differences were found in both number and length of the lineaments recognized by the different investigators for the images. The actual coincidence of lineaments recognized by the investigators for the same image is exceptionally low. Even the directional data on lineament orientation is significantly different from operator to operator and from image to image. Cluster analysis of the orientation data displays a clustering by operators rather than by images. It is recommended that extreme caution be taken before attempting to compare different investigators' results in lineament analysis.

Operational Efficiency And Customer Satisfaction of Restaurants: Basis For Business Operation Enhancement

Directory of Open Access Journals (Sweden)

Annie Gay Barlan-Espino

2017-02-01

Full Text Available Restaurants’ primary objective is to provide comfort and satisfaction to guest without compromising the operational efficiency of the business. This research aimed to determine the operational efficiency and customer satisfaction of restaurants as a basis for business operation enhancement. Specifically to determine the operational efficiency of the restaurant in terms of kitchen operations and dining operations and the level of customer satisfaction of the restaurant business in terms of: Product, Policies, People, Processes and Proactivity as well as the problems encountered by the restaurant in their operation and customer service. Descriptive research design was used with managers and customers as respondents of the study. It was concluded that majority of the restaurants are operating for more than a year with sufficient number of employees having enough seating capacity that accommodate large volume of customers. Restaurants are efficient on the aspect of kitchen and dining operations and sometimes encountered problems. Customers are satisfied in terms of 5 P’s. It was found out that there is no significant difference in the operational efficiency of restaurant when grouped according to profile variables. An action plan for continuous business operation enhancement on operational efficiency and customer satisfaction was proposed.

Operation of a low-level waste disposal facility and how to prevent problems in future facilities

International Nuclear Information System (INIS)

Di Sibio, R.

1985-01-01

Operation of a low-level waste facility is an ever increasing problem nationally, and specifically one that could grow to crisis proportion in Pennsylvania. There have been, nevertheless, a variety of changes over the years in the management of low level radioactive waste, particularly with regard to disposal facilities that can avert a crisis condition. A number of companies have been organized thru possible a broad range of services to the nuclear industry, including those that emphasize solidification of waste materials, engineering services, waste management, and transportation to disposal sites across the United States. This paper addresses one particular site and the problems which evolved at that site from an environmental perspective. It is important that it is clearly understood that, although these problems are resolvable, the lessons learned here are critical for the prevention of problems at future facilities. The focus of this paper is on the Maxey Flats, Kentucky disposal facility which was closed in 1977. It must be understood that the regulations for siting, management, burial techniques, waste classification, and the overall management of disposal sites were limited when this facility was in operation

REAL TIME MEASUREMENT OF ULTRAFINE AND NANO PARTICLES AND SIGNIFICANCE OF OPERATING GEARS

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H. A. NAKHAWA

2017-03-01

Full Text Available This research paper focuses on characterization of ultrafine and nanoparticle emissions from diesel vehicle to investigate their physical characterization in terms of number and size as they are more vulnerable and responsible for toxicity, mutagenicity and carcinogenicity. An investigation has been carried out to identify the significance of different operating gears, clutch, declutch and gear change operations for their contributions to particle number(PN on urban and extra urban part of the driving cycle. A bi-modal particle size distribution pattern was observed for both urban and extra urban parts where almost all the particles are below 200 nm and particle number peaks appear at 7 to 8 nm and at 70 nm. Nano particles contribute approximately, 70% of total particle number over urban part. Experimental investigation shows that the most significant gear for their contribution to particle number are 3rd and 5th gears on urban and extra urban part of the driving cycle respectively.

Decision support system for the operating room rescheduling problem.

Science.gov (United States)

van Essen, J Theresia; Hurink, Johann L; Hartholt, Woutske; van den Akker, Bernd J

2012-12-01

Due to surgery duration variability and arrivals of emergency surgeries, the planned Operating Room (OR) schedule is disrupted throughout the day which may lead to a change in the start time of the elective surgeries. These changes may result in undesirable situations for patients, wards or other involved departments, and therefore, the OR schedule has to be adjusted. In this paper, we develop a decision support system (DSS) which assists the OR manager in this decision by providing the three best adjusted OR schedules. The system considers the preferences of all involved stakeholders and only evaluates the OR schedules that satisfy the imposed resource constraints. The decision rules used for this system are based on a thorough analysis of the OR rescheduling problem. We model this problem as an Integer Linear Program (ILP) which objective is to minimize the deviation from the preferences of the considered stakeholders. By applying this ILP to instances from practice, we determined that the given preferences mainly lead to (i) shifting a surgery and (ii) scheduling a break between two surgeries. By using these changes in the DSS, the performed simulation study shows that less surgeries are canceled and patients and wards are more satisfied, but also that the perceived workload of several departments increases to compensate this. The system can also be used to judge the acceptability of a proposed initial OR schedule.

Ensemble Kalman Filtering with Residual Nudging: An Extension to State Estimation Problems with Nonlinear Observation Operators

KAUST Repository

Luo, Xiaodong

2014-10-01

The ensemble Kalman filter (EnKF) is an efficient algorithm for many data assimilation problems. In certain circumstances, however, divergence of the EnKF might be spotted. In previous studies, the authors proposed an observation-space-based strategy, called residual nudging, to improve the stability of the EnKF when dealing with linear observation operators. The main idea behind residual nudging is to monitor and, if necessary, adjust the distances (misfits) between the real observations and the simulated ones of the state estimates, in the hope that by doing so one may be able to obtain better estimation accuracy. In the present study, residual nudging is extended and modified in order to handle nonlinear observation operators. Such extension and modification result in an iterative filtering framework that, under suitable conditions, is able to achieve the objective of residual nudging for data assimilation problems with nonlinear observation operators. The 40-dimensional Lorenz-96 model is used to illustrate the performance of the iterative filter. Numerical results show that, while a normal EnKF may diverge with nonlinear observation operators, the proposed iterative filter remains stable and leads to reasonable estimation accuracy under various experimental settings.

The role of crossover operator in evolutionary-based approach to the problem of genetic code optimization.

Science.gov (United States)

Błażej, Paweł; Wnȩtrzak, Małgorzata; Mackiewicz, Paweł

2016-12-01

One of theories explaining the present structure of canonical genetic code assumes that it was optimized to minimize harmful effects of amino acid replacements resulting from nucleotide substitutions and translational errors. A way to testify this concept is to find the optimal code under given criteria and compare it with the canonical genetic code. Unfortunately, the huge number of possible alternatives makes it impossible to find the optimal code using exhaustive methods in sensible time. Therefore, heuristic methods should be applied to search the space of possible solutions. Evolutionary algorithms (EA) seem to be ones of such promising approaches. This class of methods is founded both on mutation and crossover operators, which are responsible for creating and maintaining the diversity of candidate solutions. These operators possess dissimilar characteristics and consequently play different roles in the process of finding the best solutions under given criteria. Therefore, the effective searching for the potential solutions can be improved by applying both of them, especially when these operators are devised specifically for a given problem. To study this subject, we analyze the effectiveness of algorithms for various combinations of mutation and crossover probabilities under three models of the genetic code assuming different restrictions on its structure. To achieve that, we adapt the position based crossover operator for the most restricted model and develop a new type of crossover operator for the more general models. The applied fitness function describes costs of amino acid replacement regarding their polarity. Our results indicate that the usage of crossover operators can significantly improve the quality of the solutions. Moreover, the simulations with the crossover operator optimize the fitness function in the smaller number of generations than simulations without this operator. The optimal genetic codes without restrictions on their structure

Inverse source problem and null controllability for multidimensional parabolic operators of Grushin type

International Nuclear Information System (INIS)

Beauchard, K; Cannarsa, P; Yamamoto, M

2014-01-01

The approach to Lipschitz stability for uniformly parabolic equations introduced by Imanuvilov and Yamamoto in 1998 based on Carleman estimates, seems hard to apply to the case of Grushin-type operators of interest to this paper. Indeed, such estimates are still missing for parabolic operators degenerating in the interior of the space domain. Nevertheless, we are able to prove Lipschitz stability results for inverse source problems for such operators, with locally distributed measurements in an arbitrary space dimension. For this purpose, we follow a mixed strategy which combines the approach due to Lebeau and Robbiano, relying on Fourier decomposition and Carleman inequalities for heat equations with non-smooth coefficients (solved by the Fourier modes). As a corollary, we obtain a direct proof of the observability of multidimensional Grushin-type parabolic equations, with locally distributed observations—which is equivalent to null controllability with locally distributed controls. (paper)

Human errors in NPP operations

International Nuclear Information System (INIS)

Sheng Jufang

1993-01-01

Based on the operational experiences of nuclear power plants (NPPs), the importance of studying human performance problems is described. Statistical analysis on the significance or frequency of various root-causes and error-modes from a large number of human-error-related events demonstrate that the defects in operation/maintenance procedures, working place factors, communication and training practices are primary root-causes, while omission, transposition, quantitative mistake are the most frequent among the error-modes. Recommendations about domestic research on human performance problem in NPPs are suggested

Solvability of fractional multi-point boundary-value problems with p-Laplacian operator at resonance

Directory of Open Access Journals (Sweden)

Tengfei Shen

2014-02-01

Full Text Available In this article, we consider the multi-point boundary-value problem for nonlinear fractional differential equations with $p$-Laplacian operator: $$\\displaylines{ D_{0^+}^\\beta \\varphi_p (D_{0^+}^\\alpha u(t = f(t,u(t,D_{0^+}^{\\alpha - 2} u(t,D_{0^+}^{\\alpha - 1} u(t, D_{0^+}^\\alpha u(t,\\quad t \\in (0,1, \\cr u(0 = u'(0=D_{0^+}^\\alpha u(0 = 0,\\quad D_{0^+}^{\\alpha - 1} u(1 = \\sum_{i = 1}^m {\\sigma_i D_{0^+}^{\\alpha - 1} u(\\eta_i } , }$$ where $2 < \\alpha \\le 3$, $0 < \\beta \\le 1$, $3 < \\alpha + \\beta \\le 4$, $\\sum_{i = 1}^m {\\sigma_i } = 1$, $D_{0^+}^\\alpha$ is the standard Riemann-Liouville fractional derivative. $\\varphi_{p}(s=|s|^{p-2}s$ is p-Laplacians operator. The existence of solutions for above fractional boundary value problem is obtained by using the extension of Mawhin's continuation theorem due to Ge, which enrich konwn results. An example is given to illustrate the main result.

Convergence rates and finite-dimensional approximations for nonlinear ill-posed problems involving monotone operators in Banach spaces

International Nuclear Information System (INIS)

Nguyen Buong.

1992-11-01

The purpose of this paper is to investigate convergence rates for an operator version of Tikhonov regularization constructed by dual mapping for nonlinear ill-posed problems involving monotone operators in real reflective Banach spaces. The obtained results are considered in combination with finite-dimensional approximations for the space. An example is considered for illustration. (author). 15 refs

Modeling Multioperator Multi-UAV Operator Attention Allocation Problem Based on Maximizing the Global Reward

Directory of Open Access Journals (Sweden)

Yuhang Wu

2016-01-01

Full Text Available This paper focuses on the attention allocation problem (AAP in modeling multioperator multi-UAV (MOMU, with the operator model and task properties taken into consideration. The model of MOMU operator AAP based on maximizing the global reward is established and used to allocate tasks to all operators as well as set work time and rest time to each task simultaneously for operators. The proposed model is validated in Matlab simulation environment, using the immune algorithm and dynamic programming algorithm to evaluate the performance of the model in terms of the reward value with regard to the work time, rest time, and task allocation. The result shows that the total reward of the proposed model is larger than the one obtained from previously published methods using local maximization and the total reward of our method has an exponent-like relation with the task arrival rate. The proposed model can improve the operators’ task processing efficiency in the MOMU command and control scenarios.

How are things adding up? Neural differences between arithmetic operations are due to general problem solving strategies.

Science.gov (United States)

Tschentscher, Nadja; Hauk, Olaf

2014-05-15

A number of previous studies have interpreted differences in brain activation between arithmetic operation types (e.g. addition and multiplication) as evidence in favor of distinct cortical representations, processes or neural systems. It is still not clear how differences in general task complexity contribute to these neural differences. Here, we used a mental arithmetic paradigm to disentangle brain areas related to general problem solving from those involved in operation type specific processes (addition versus multiplication). We orthogonally varied operation type and complexity. Importantly, complexity was defined not only based on surface criteria (for example number size), but also on the basis of individual participants' strategy ratings, which were validated in a detailed behavioral analysis. We replicated previously reported operation type effects in our analyses based on surface criteria. However, these effects vanished when controlling for individual strategies. Instead, procedural strategies contrasted with memory retrieval reliably activated fronto-parietal and motor regions, while retrieval strategies activated parietal cortices. This challenges views that operation types rely on partially different neural systems, and suggests that previously reported differences between operation types may have emerged due to invalid measures of complexity. We conclude that mental arithmetic is a powerful paradigm to study brain networks of abstract problem solving, as long as individual participants' strategies are taken into account. Copyright © 2014 Elsevier Inc. All rights reserved.

Types of motivating operations in interventions with problem behavior: a systematic review.

Science.gov (United States)

Simó-Pinatella, David; Font-Roura, Josep; Planella-Morató, Joaquima; McGill, Peter; Alomar-Kurz, Elisabeth; Giné, Climent

2013-01-01

A motivating operation (MO) alters both the effectiveness of a stimulus as a reinforcer and the current frequency of all behavior that has been reinforced by that particular stimulus. This article reviews studies that have manipulated a MO during interventions with school-age participants with intellectual disabilities and problem behavior. A systematic review was conducted using the following major electronic databases: PsychInfo, Education Resources Information Center, Science Direct, Blackwell, SAGE, and Medline. A total of 31 published articles representing 55 participants was examined. Findings from this study suggest that the modification of a MO usually has an effect on the problem behavior by either establishing or abolishing its motivation. Furthermore, a relationship was found between the type of MO and the behavioral function identified. The theoretical and practical implications of these findings, limitations of this study and potential issues for future research are discussed.

Cognitive modeling and dynamic probabilistic simulation of operating crew response to complex system accidents. Part 4: IDAC causal model of operator problem-solving response

Energy Technology Data Exchange (ETDEWEB)

Chang, Y.H.J. [Center for Risk and Reliability, University of Maryland, College Park, MD 20742 (United States) and Paul Scherrer Institute, 5232 Villigen PSI (Switzerland)]. E-mail: yhc@umd.edu; Mosleh, A. [Center for Risk and Reliability, University of Maryland, College Park, MD 20742 (United States)

2007-08-15

This is the fourth in a series of five papers describing the Information, Decision, and Action in Crew context (IDAC) operator response model for human reliability analysis. An example application of this modeling technique is also discussed in this series. The model has been developed to probabilistically predicts the responses of a nuclear power plant control room operating crew in accident conditions. The operator response spectrum includes cognitive, emotional, and physical activities during the course of an accident. This paper assesses the effects of the performance-influencing factors (PIFs) affecting the operators' problem-solving responses including information pre-processing (I), diagnosis and decision making (D), and action execution (A). Literature support and justifications are provided for the assessment on the influences of PIFs.

Cognitive modeling and dynamic probabilistic simulation of operating crew response to complex system accidents. Part 4: IDAC causal model of operator problem-solving response

International Nuclear Information System (INIS)

Chang, Y.H.J.; Mosleh, A.

2007-01-01

This is the fourth in a series of five papers describing the Information, Decision, and Action in Crew context (IDAC) operator response model for human reliability analysis. An example application of this modeling technique is also discussed in this series. The model has been developed to probabilistically predicts the responses of a nuclear power plant control room operating crew in accident conditions. The operator response spectrum includes cognitive, emotional, and physical activities during the course of an accident. This paper assesses the effects of the performance-influencing factors (PIFs) affecting the operators' problem-solving responses including information pre-processing (I), diagnosis and decision making (D), and action execution (A). Literature support and justifications are provided for the assessment on the influences of PIFs

Spectral methods for a nonlinear initial value problem involving pseudo differential operators

International Nuclear Information System (INIS)

Pasciak, J.E.

1982-01-01

Spectral methods (Fourier methods) for approximating the solution of a nonlinear initial value problem involving pseudo differential operators are defined and analyzed. A semidiscrete approximation to the nonlinear equation based on an L 2 projection is described. The semidiscrete L 2 approximation is shown to be a priori stable and convergent under sufficient decay and smoothness assumptions on the initial data. It is shown that the semidiscrete method converges with infinite order, that is, higher order decay and smoothness assumptions imply higher order error bounds. Spectral schemes based on spacial collocation are also discussed

A Heuristic Procedure for the Outbound Container Relocation Problem during Export Loading Operations

Directory of Open Access Journals (Sweden)

Roberto Guerra-Olivares

2015-01-01

Full Text Available During export ship loading operations, it is often necessary to perform relocation movements with containers that interfere with access to the desired container in the ship loading sequence. This paper presents a real-time heuristic procedure for the container relocation problem employing reachstacker vehicles as container handling equipment. The proposed heuristic searches for good relocation coordinates within a set of nearby bays. The heuristic has a parameter that determines how far from the original bay a container may be relocated. The tradeoff between reducing relocation movements and limiting vehicle travel distances is examined and the performance of the heuristic is compared with a common practice in the smaller container terminals in Chile and Mexico. Finally, a mathematical model for the container relocation problem is presented.

Incremental artificial bee colony with local search to economic dispatch problem with ramp rate limits and prohibited operating zones

International Nuclear Information System (INIS)

Özyön, Serdar; Aydin, Doğan

2013-01-01

Highlights: ► Prohibited operating zone economic dispatch problem has been solved by IABC-LS. ► The losses used in the solution of the problem have been computed by B-loss matrix. ► IABC-LS method has been applied to three test systems in literature. ► The values obtained by IABC and IABC-LS are better than the results in literature. - Abstract: In this study, prohibited operating zone economic power dispatch problem which considers ramp rate limit, has been solved by incremental artificial bee colony algorithm (IABC) and incremental artificial bee colony algorithm with local search (IABC-LS) methods. The transmission line losses used in the solution of the problem have been computed by B-loss matrix. IABC, IABC-LS methods have been applied to three different test systems in literature which consist of 6, 15 and 40 generators. The attained optimum solution values have been compared with the optimum results in literature and have been discussed.

Economic Operation of Power Systems with Significant Wind Power Penetration

DEFF Research Database (Denmark)

Farashbashi-Astaneh, Seyed-Mostafa

This dissertation addresses economic operation of power systems with high penetration of wind power. Several studies are presented to address the economic operation of power systems with high penetration of variable wind power. The main concern in such power systems is high variability...... and unpredictability. Unlike conventional power plants, the output power of a wind farm is not controllable. This brings additional complexity to operation and planning of wind dominant power systems. The key solution in face of wind power uncertainty is to enhance power system flexibility. The enhanced flexibility......, cooperative wind-storage operation is studied. Lithium-Ion battery units are chosen as storage units. A novel formulation is proposed to investigate optimal operation of a storage unit considering power system balancing conditions and wind power imbalances. An optimization framework is presented to increase...

Visual Problems in Night Operations (Problemes de Vision dans les Operations de Nuit)

Science.gov (United States)

1992-05-01

conference proceedings (FR) Progrqbs r~cents concernant l05 aides au pilote clans I habitacle d’un aaroi’ef milltaire en operations. Nouveau drone ...allleurs) traitelit doe la sophistication des La firme isra~lienne tAt teste un nouveau drone appel6 ’Impact’. tacnes domanda~es aus pilotes d-avionS- doe...une camara do tala6vision A vision nocturne. 151 met aussl relations liomlme-macfline.ces syst~mws (lndiff~remesmnt dasignds au point une station

Complication amoebic liver abscess still a significant health problem ...

African Journals Online (AJOL)

Amoebic liver abscess still poses a serious clinical problem in tropical countries. Here we describe three complicated cases to illustrate the magnitude this disease condition could assume in the tropics. Limited access to health facilities as well as poverty and ignorance result in patients presenting late, often with ...

Categorization of safety related motor operated valve safety significance for Ulchin Unit 3

International Nuclear Information System (INIS)

Kang, D. I.; Kim, K. Y.

2002-03-01

We performed a categorization of safety related Motor Operated Valve (MOV) safety significance for Ulchin Unit 3. The safety evaluation of MOV of domestic nuclear power plants affects the generic data used for the quantification of MOV common cause failure ( CCF) events in Ulchin Units 3 PSA. Therefore, in this study, we re-estimated the MGL(Multiple Greek Letter) parameter used for the evaluation of MOV CCF probabilities in Ulchin Units 3 Probabilistic Safety Assessment (PSA) and performed a classification of the MOV safety significance. The re-estimation results of the MGL parameter show that its value is decreased by 30% compared with the current value in Ulchin Unit 3 PSA. The categorization results of MOV safety significance using the changed value of MGL parameter shows that the number of HSSCs(High Safety Significant Components) is decreased by 54.5% compared with those using the current value of it in Ulchin Units 3 PSA

Explanation of significant differences for the TNX groundwater operable unit

International Nuclear Information System (INIS)

Palmer, E.R.

1997-01-01

This Explanation of Significant Differences (ESD) is being issued by the Department of Energy (DOE), the lead agency for the Savannah River Site (SRS), with concurrence by the Environmental Protection Agency-Region IV (EPA) and South Carolina Department of Health and Environmental Control (SCDHEC) to announce changes in the interim remediation strategy selected for the TNX Groundwater Operable Unit. The TNX Area is located adjacent to the Savannah River in the southwestern portion of SRS. The remedy selected in the Interim Record of Decision (IROD) to achieve the interim action goals was the Hybrid Groundwater Corrective Action (HGCA). The HGCA consisted of a recirculation well system and an air stripper with a series of groundwater extraction wells. The original remediation strategy needs to be modified because the recirculation well system was determined to be ineffective in this area due to geological factors and the nature of the contamination

The problem of maintenance of strength, lifetime and safety of the structural components operational NPP from items of a system approach

International Nuclear Information System (INIS)

Getman, A.F.

2005-01-01

The strength of the structural components and pipelines NPP determines largely their lifetime, radiation and nuclear safety. As shows world experience of operation NPP, in a series of cases during operation the local damages, breaks and destructions of elements of the equipment and pipelines emerge. These cases force maintaining organizations to execute on NPP large volumes of the control, repair and modernizing of the equipment and pipelines. These activities require large material inputs (net less than 50% of the cost of operation NPP), however not always are effective and in a series of cases do not allow to reach required of level reliability and safety. The reason of such condition of a problem is that the measures executed on NPP, developed on stretch of long time and under influence of the diverse factors. Besides until now there is no unified scientific methodology of a case study of maintenance of strength, lifetime and safety of the operational equipment and pipelines NPP. The application of a system approach to a problem of maintenance of strength, lifetime and safety of the equipment and pipelines operational NPP allows to consider a problem as a whole, from unified items, to define the most fast and effective paths it of the solution and to decide problems in as much as possible short times at minimum material inputs. The experience of practical application of a system approach at the solution of separate problems of operation NPP has allowed to develop a lot of effective new techniques, technologies and means, which application allows essentially to increase reliability and gamma percentage lifetime of elements NPP, to which they were applied. As an example in the report the outcomes of application of a system approach for maintenance of SG tubes integrity of reactors of a type WWER are adduced. The application of a system approach for all elements of the equipment and pipelines NPP will allow to increase it reliability and safety not less, than on 10

Triple solutions for a Dirichlet boundary value problem involving a perturbed discrete p(k-Laplacian operator

Directory of Open Access Journals (Sweden)

Khaleghi Moghadam Mohsen

2017-08-01

Full Text Available Triple solutions are obtained for a discrete problem involving a nonlinearly perturbed one-dimensional p(k-Laplacian operator and satisfying Dirichlet boundary conditions. The methods for existence rely on a Ricceri-local minimum theorem for differentiable functionals. Several examples are included to illustrate the main results.

Applications of ordered weighted averaging (OWA operators in environmental problems

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Carlos Llopis-Albert

2017-04-01

Full Text Available This paper presents an application of a prioritized weighted aggregation operator based on ordered weighted averaging (OWA to deal with stakeholders' constructive participation in water resources projects. They have different degree of acceptance or preference regarding the measures and policies to be carried out, which lead to different environmental and socio-economic outcomes, and hence, to different levels of stakeholders’ satisfaction. The methodology establishes a prioritization relationship upon the stakeholders, which preferences are aggregated by means of weights depending on the satisfaction of the higher priority policy maker. The methodology establishes a prioritization relationship upon the stakeholders, which preferences are aggregated by means of weights depending on the satisfaction of the higher priority policy maker. The methodology has been successfully applied to a Public Participation Project (PPP in watershed management, thus obtaining efficient environmental measures in conflict resolution problems under actors’ preference uncertainties.

Compressed modes for variational problems in mathematical physics and compactly supported multiresolution basis for the Laplace operator

Science.gov (United States)

Ozolins, Vidvuds; Lai, Rongjie; Caflisch, Russel; Osher, Stanley

2014-03-01

We will describe a general formalism for obtaining spatially localized (``sparse'') solutions to a class of problems in mathematical physics, which can be recast as variational optimization problems, such as the important case of Schrödinger's equation in quantum mechanics. Sparsity is achieved by adding an L1 regularization term to the variational principle, which is shown to yield solutions with compact support (``compressed modes''). Linear combinations of these modes approximate the eigenvalue spectrum and eigenfunctions in a systematically improvable manner, and the localization properties of compressed modes make them an attractive choice for use with efficient numerical algorithms that scale linearly with the problem size. In addition, we introduce an L1 regularized variational framework for developing a spatially localized basis, compressed plane waves (CPWs), that spans the eigenspace of a differential operator, for instance, the Laplace operator. Our approach generalizes the concept of plane waves to an orthogonal real-space basis with multiresolution capabilities. Supported by NSF Award DMR-1106024 (VO), DOE Contract No. DE-FG02-05ER25710 (RC) and ONR Grant No. N00014-11-1-719 (SO).

Is Late or Non-Payment a Significant Problem to Malaysian Contractors?

OpenAIRE

M.E. Che Munaaim; M.S. Mohd Danuri; H. Abdul-Rahman

2007-01-01

Some developed countries have drawn lip construction-specific statutory security of payment acts/legislations typically known as Construction Contracts Act to eliminate poor payment practices and to assist continuous uninterrupted construction works. Malaysia too cannot pretend not to have these problems. This paper presents findings of a study conducted amongst Malaysian contractors with the aims to determine the seriousness of late and non- payment problems; to identify the main causes and ...

Study of Cancelled Elective Surgical Operations

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M Amrollahi

2004-07-01

Full Text Available Introduction: Cancellation of an elective operation is a very important problem, which is the cause for different types of stresses for patients and their families and results in loss of significant amount of time, money and hospital resources. Therefore, finding the main causes of operation postponement may help us to understand and reduce these problems. Material & Method: A special questionnaire was designed to gather information about different causes of operation cancellation and filled from October 23rd (Aban 1st till November 21st (Azar 30 th, 2001 (1380 in all of the teaching hospitals of Yazd university. (S.Dr Rahnemoon, Afshar, Rah Ahan, Bahman and Savaneg Sukhteghy Results were statistically evaluated.. Results: 180 of the 31437 scheduled operations had been cancelled (12.52% Majority of cases (33.3% had been cancelled due to the absence of the surgeons. This group ((Surgeons absent was the most common cause for the postponement of operations (36.7%. The secondary cause of cancellations was related to anesthetic team and operating room problems (25%, the patient’s reasons for cancellation was 16.2% and the most minimal cause of cancellation was insufficient hospital revenue (0.5%. The basis of disease or high risk patients for operation were the main causes of dysfunction of the anesthetic team (68.9% and also the first cause of cancellation. The rate of cancellation was the most in the "older than 60 years" age group. (15.4% The cancellation in women was 12.6% and in males 12.5%. Conclusion: Surgeons schedule more patients keeping in mind cancellations which occur regularly due to patients, hospital, anesthesia, and operating room problems. This over scheduling is a problem itself, so preadmission evaluation clinics are recommended to decrease the rate of cancellations thereby saving the socioeconomic resources and decreasing patient’s stress.

Operant Conditioning Principles in the Treatment of Learning and Behavior Problems with Delinquent Boys

Science.gov (United States)

Bednar, Richard L.; And Others

1970-01-01

This study on operant conditioning showed that both groups showed significant improvement in reading skills from pretest to posttest, but that the reinforced group showed significantly more improvement than the nonreinforced group. (Author)

Is Late or Non-Payment a Significant Problem to Malaysian Contractors?

Directory of Open Access Journals (Sweden)

M.E. Che Munaaim

2007-12-01

Full Text Available Some developed countries have drawn lip construction-specific statutory security of payment acts/legislations typically known as Construction Contracts Act to eliminate poor payment practices and to assist continuous uninterrupted construction works. Malaysia too cannot pretend not to have these problems. This paper presents findings of a study conducted amongst Malaysian contractors with the aims to determine the seriousness of late and non- payment problems; to identify the main causes and effects of late and non-payment; and to identify ways to sustain the payment flows in the Malaysian construction industry. The study focused on contractual payments from the paymaster (government or private to the contractors. The main factors for late and nonpayment in the construction industry identified from the study include: delay in certification, paymaster's poor financial management, local culture/attitude, pay master's failure to implement good governance in business, underpayment of certified amounts by the pay master and the use of 'pay when paid' clauses in contracts. The research findings show that late and non-payment can create cash flow problems, stress and financial hardship on the contractors. Amongst the most appropriate solutions to overcome the problem of late and non-payment faced by local contractors include: a right to regular periodic payment, a right to a defined time frame (or payment and a right to a speedy dispute resolution mechanism. Promptness of submitting, processing, issuing interim payment certificates and honouring the certificates are extremely important issues in relation to progress payment claims. Perhaps, an increased sense of professionalism in construction industry could overcome some of the problems related to late and non- payment issues.

Fast Combinatorial Algorithm for the Solution of Linearly Constrained Least Squares Problems

Science.gov (United States)

Van Benthem, Mark H.; Keenan, Michael R.

2008-11-11

A fast combinatorial algorithm can significantly reduce the computational burden when solving general equality and inequality constrained least squares problems with large numbers of observation vectors. The combinatorial algorithm provides a mathematically rigorous solution and operates at great speed by reorganizing the calculations to take advantage of the combinatorial nature of the problems to be solved. The combinatorial algorithm exploits the structure that exists in large-scale problems in order to minimize the number of arithmetic operations required to obtain a solution.

The Effects of 10 Communication Modes on the Behavior of Teams During Co-Operative Problem-Solving

Science.gov (United States)

Ochsman, Richard B.; Chapanis, Alphonse

1974-01-01

Sixty teams of two college students each solved credible "real world" problems co-operatively. Conversations were carried on in one of 10 modes of communication: (1) typewriting only, (2) handwriting only, (3) handwriting and typewriting, (4) typewriting and video, (5) handwriting and video, (6) voice only, (7) voice and typewriting, (8) voice and…

Complications / problems of colostomy in infants and children

International Nuclear Information System (INIS)

Sheikh, M.A.; Akhtar, J.; Ahmed, S.

2006-01-01

To determine the frequency of complications/problems occurring with construction of colostomy in infants and children. All the patients admitted in the unit who required colostomy as part of their management were included in the study. The patients who were operated upon previously or operated elsewhere and referred after having colostomy, were excluded. Problems associated with colostomy construction like skin excoriation and chronic blood loss were also recorded. Chi-square test of proportion was used to determine the p-value. There were 121 patients. Most of the patients were operated due to anorectal malformations (n=71) and Hirschsprung's disease (41). Complications/problems related to colostomy occurred in 67.7% patients. The most common problem was skin excoriation. Second in rating was chronic blood loss from stoma. Prolapse of stoma was more common in transverse loop colostomies. Divided colostomies had higher number of complications as compared to loop colostomies, similarly, transverse colostomies had high number of complications but in both the cases difference was not statistically significant. Four (3.3%) patients died. (author)

PSYCHOLOGICAL PROBLEMS AND STRESS FACED BY SOLDIERS WHO OPERATE IN ASYMMETRIC WARFARE ENVIRONMENTS: EXPERIENCES IN THE FIELD

Directory of Open Access Journals (Sweden)

Giuseppe CAFORIO

2014-10-01

Full Text Available This article deals with the problems of anxiety, stress and psychological discomfort that can affect soldiers sent on asymmetric warfare operations. It is based on secondary analysis of the data of two important field researches whose results have recently (2013 been published. Although the two researches adopted different methodologies, the testimonies are fully comparable and show that soldiers from different countries and cultures display common or similar reactions when they are placed in the stress conditions that the asymmetric environment involves. The approach of the paper is drawn up in such a way as to make the reader a participating observer of the reality of such missions. It is therefore centered on the personal testimonies of the soldiers interviewed in the two researches, testimonies reported just as they are, in their simplicity and, often, drama, with comments by the author kept to a minimum in order to give readers ample opportunity to evaluate and interpret the reported texts on their own. The research data, drawn from the declarations of those directly concerned, reveal the existence of a problem of psychological distress resulting from deployment in asymmetric warfare situations that is in part different in the causes of the problems resulting from deployment in traditional combat and affects percentages of participating soldiers that are not high but definitely significant. The highest incidence appears to be constituted by problems relating to reintegration into normal social and working life upon returning from the mission. This is followed in percentage terms by anxiety situations relating to life far from the family, due in large part to a sense of powerlessness for the scant possibility of managing family situations that may have cropped up or already existed beforehand.

On the solution of the inverse scattering problem for the quadratic bundle of the one-dimensional Schroedinger operators of the whole axis

International Nuclear Information System (INIS)

Maksudov, F.G.; Gusejnov, G.Sh.

1986-01-01

Inverse scattering problem for the quadratic bundle of the Schroedinger one-dimensional operators in the whole axis is solved. The problem solution is given on the assumption of the discrete spectrum absence. In the discrete spectrum presence the inverse scattering problem solution is known for the Shroedinger differential equation considered

Nonlocal Operational Calculi for Dunkl Operators

Directory of Open Access Journals (Sweden)

Ivan H. Dimovski

2009-03-01

Full Text Available The one-dimensional Dunkl operator $D_k$ with a non-negative parameter $k$, is considered under an arbitrary nonlocal boundary value condition. The right inverse operator of $D_k$, satisfying this condition is studied. An operational calculus of Mikusinski type is developed. In the frames of this operational calculi an extension of the Heaviside algorithm for solution of nonlocal Cauchy boundary value problems for Dunkl functional-differential equations $P(D_ku = f$ with a given polynomial $P$ is proposed. The solution of these equations in mean-periodic functions reduces to such problems. Necessary and sufficient condition for existence of unique solution in mean-periodic functions is found.

Radiation protection problems by the operation of the cyclotron facility

International Nuclear Information System (INIS)

Durcik, M.; Nikodemova, D.

1998-01-01

The Cyclotron Center in Bratislava will consist of two cyclotrons. First - cyclotron DC-72 with maximal energy of 72 MV for protons for making experiments, for teaching process, for radioisotope production as 123 I and for neutron and proton therapy. Second - compact cyclotron with maximal proton energy of 18 MeV will be used for radioisotopes production for medical diagnosis as 1 *F (fluorodeoxyglucose), 81 Rb/ 81 Kr generator. This paper deals with the radiation protection problems by the operation of tis cyclotron facility as radiation protection of workers, monitoring plan, ventilation, safety lock and limitation and radiation monitoring. For proposed and continuing practices at the accelerator facility, the following general principles have to be fulfilled: (1) practices should produce sufficient benefit to offset the radiation detriment they case (justification); (2) the magnitude of the individual doses should be kept as low as achievable (optimization of protection); (3) individual exposures are subject to dose limits and some control of risk from potential exposures (dose and risk limits)

Studying the effects of operators' problem solving behaviour when using a diagnostic expert system developed for the nuclear industry

International Nuclear Information System (INIS)

Holmstroem, C.B.O.; Volden, F.S.; Endestad, T.

1992-01-01

This paper describes an experiment with the purpose to also illustrate and discuss some of the methodological problems when empirically studying problem solving. The experiment which was the second in a series, conducted at the OECD Halden Reactor Project, aimed to assess the effect on nuclear power plant operators diagnostic behaviour when using a rule-based diagnostic expert system. The rule-based expert system used in the experiment is called DISKET (Diagnosis System Using Knowledge Engineering Technique) and was originally developed by the Japan Atomic Energy Research Institute (JAERI). The experiment was performed in the Halden man-machine laboratory using a full scope pressurized water reactor simulator. Existing data collection methods and experimental design principles includes possibilities but also limitations. This is discussed and experiences are presented. Operator performance in terms of quality of diagnosis is improved by the use of DISKET. The use of the DISKET system also influences operators problem solving behaviour. The main difference between the two experimental conditions can be characterized as while the DISKET users during the diagnosis process are following a strategy which is direct and narrowed, the non-DISKET users are using a much broader and less focused search when trying to diagnose a disturbance. (author)

De la Vallee Poussin problem in the kernel of the convolution operator on the half-plane

Directory of Open Access Journals (Sweden)

Valentin V. Napalkov

2015-06-01

Full Text Available We consider the multipoint de la Vallee Poussin (interpolational problem in the half-plane $D$, $D=ż  :  \\mathop{\\mathrm{Re}} z0\\}$. Let $\\psi(z\\in H(D$; $\\mu_1$, $\\mu_2$, $\\ldots \\in D$ be the positive zero points of this function and let the boundary of domain $D$ contain their limit. Also, we assume that $\\mu_k$ is of $s_k$ multiplicity, $k=1, 2, …$. Let us set $M_{\\varphi}$ an operator of convolution with the characteristic function $\\varphi(z$. Taking an arbitrary sequence $a_{kj},$ $j=0, 1, \\ldots, s_k-1$ we should ask: is there a function $u(z \\in \\mathop{\\mathrm{Ker}}M_\\varphi$ that provides the relation $u^{(j}(\\mu_{k}=a_{kj},$ $j=0, 1,…,s_k-1$? We assume the operator characteristic function to be of completely regular growth. The solvability conditions for the multipoint de la Vallée Poussin problem in the half-plain and in the bounded convex domains are obtained.

Thermal fluctuation problems encountered in LMFRs

International Nuclear Information System (INIS)

Gelineau, O.; Sperandio, M.; Martin, P.; Ricard, J.B.; Martin, L.; Bougault, A.

1994-01-01

One of the most significant problems of LMFBRs deals with thermal fluctuations. The main reason is that LMFBRs operate with sodium coolant at very different temperatures which leads to the existence of several areas of transition between hot and cold sodium. These transitions areas which are the critical points, maybe found in the reactor block as well as in the secondary and auxiliary loops. The characteristics of these thermal fluctuations are not easy to quantify because of their complex (random) behaviour, and often demand the use of thermalhydraulic mock-up tests. A good knowledge of these phenomena is essential because of the potential high level of damage they can induce on structures. Two typical thermal fluctuation problems encountered on operation reactors are described. They were not originally anticipated at the design stage of the former Phenix and the latter Superphenix reactors. Description and the analyses performed to describe the damaging process are explained. A well known thermal fluctuation problem is presented. It is pointed out how the feedback from the damages observed on operating reactors is used to prevent the components from any high cycle fatigue

The Development of an Internet-Based Treatment for Problem Gamblers and Concerned Significant Others: A Pilot Randomized Controlled Trial.

Science.gov (United States)

Nilsson, Anders; Magnusson, Kristoffer; Carlbring, Per; Andersson, Gerhard; Gumpert, Clara Hellner

2018-06-01

Problem gambling creates significant harm for the gambler and for concerned significant others (CSOs). While several studies have investigated the effects of individual cognitive behavioral therapy (CBT) for problem gambling, less is known about the effects of involving CSOs in treatment. Behavioral couples therapy (BCT) has shown promising results when working with substance use disorders by involving both the user and a CSO. This pilot study investigated BCT for problem gambling, as well as the feasibility of performing a larger scale randomized controlled trial. 36 participants, 18 gamblers and 18 CSOs, were randomized to either BCT or individual CBT for the gambler. Both interventions were Internet-delivered self-help interventions with therapist support. Both groups of gamblers improved on all outcome measures, but there were no differences between the groups. The CSOs in the BCT group lowered their scores on anxiety and depression more than the CSOs of those randomized to the individual CBT group did. The implications of the results and the feasibility of the trial are discussed.

Dresses problems arising from hot-plant operation and their solution (1961)

International Nuclear Information System (INIS)

Rodier, J.; Bouzigues, H.; Boutot, P.

1961-01-01

This article deals with effective methods to struggle radioactive contamination using rationally designed working clothes. The choice of the cloth is important and cotton, because of its absorbent properties constitutes an effective barrier to radioelements failing on its surface. Clothing the personnel of large nuclear industrial concerns is a big problem which can only be solved by carefully studied methods. The decontamination and washing of large amounts of clothes whose flow increases during periods of radio-active incidents have to be treated as are those operations in hospital laundering. Linen washing by the German counter-current method (the Sulzman system) is of great value because of the volume which can be treated and, more important, because of the small amount of liquid waste produced. Dry cleaning is certainly a method of the future and is even more economic than the preceding one. In 'active' laundries, the control of clothing for residual contamination can constitute a serious bottleneck in the production of clean clothing if automatic high-speed machines are not used. The risk to the operating personnel comes solely from contamination of the atmosphere and of the surfaces. Because of this, the plant must be considered as an active zone in which are handled several tens of millicuries of dangerous emitters and several micro- curies of plutonium daily. (authors) [fr

Report to NASA Committee on Aircraft Operating Problems Relative to Aviation Safety Engineering and Research Activities

Science.gov (United States)

1963-01-01

The following report highlights some of the work accomplished by the Aviation Safety Engineering and Research Division of the Flight Safety Foundations since the last report to the NASA Committee on Aircraft Operating Problems on 22 May 1963. The information presented is in summary form. Additional details may be provided upon request of the reports themselves may be obtained from AvSER.

Identifying indicators of harmful and problem gambling in a Canadian sample through receiver operating characteristic analysis.

Science.gov (United States)

Quilty, Lena C; Avila Murati, Daniela; Bagby, R Michael

2014-03-01

Many gamblers would prefer to reduce gambling on their own rather than to adopt an abstinence approach within the context of a gambling treatment program. Yet responsible gambling guidelines lack quantifiable markers to guide gamblers in wagering safely. To address these issues, the current investigation implemented receiver operating characteristic (ROC) analysis to identify behavioral indicators of harmful and problem gambling. Gambling involvement was assessed in 503 participants (275 psychiatric outpatients and 228 community gamblers) with the Canadian Problem Gambling Index. Overall gambling frequency, duration, and expenditure were able to distinguish harmful and problematic gambling at a moderate level. Indicators of harmful gambling were generated for engagement in specific gambling activities: frequency of tickets and casino; duration of bingo, casino, and investments; and expenditures on bingo, casino, sports betting, games of skill, and investments. Indicators of problem gambling were similarly produced for frequency of tickets and casino, and expenditures on bingo, casino, games of skill, and investments. Logistic regression analyses revealed that overall gambling frequency uniquely predicted the presence of harmful and problem gambling. Furthermore, frequency indicators for tickets and casino uniquely predicted the presence of both harmful and problem gambling. Together, these findings contribute to the development of an empirically based method enabling the minimization of harmful or problem gambling through self-control rather than abstinence.

Main problems experienced on diesel generators of French 900 MWe operating units

Energy Technology Data Exchange (ETDEWEB)

Dredemis, Geoffroy; Jude, Francois [Commissariat a l' Energie Atomique, centre d' Etudes Nucleaires de Fontenay-aux-Roses, Institut de Protection et Surete Nucleaire, Departement d' Analyse de Surete, B.P. No. 6, 92260 Fontenay-aux-Roses (France)

1986-02-15

Each unit of all the French nuclear power plant is equipped with two diesel emergency generator sets., For the totality of standards PWRs of 900 MWe, they are identical. We present in this communication the most significative failures met with diesel engines on operating units, such as rupture of fuel injection pipes, breaking of the connecting rods, and cylinder lubrication failures. All these incidents, which affected the emergency power sources of concerned units, had generic characteristics. In view of their potential consequences, it was proceeded in each case to an immediate control of the components concerned of all PWR 900 MWe diesel engines. At the same time, studies were started as to what modifications would permit to solve rapidly each one of the problems met with. (authors)

Operating multireservoir hydropower systems for downstream water quality

International Nuclear Information System (INIS)

Hayes, D.F.

1990-01-01

Hydropower reservoir operations often impact tailwater quality and water quality in the stream or river below the impoundment for many miles. Determining optimal operating strategies for a system of hydropower reservoirs involves solving a highly dimensional nonlinear, nonconvex optimization problem. This research adds the additional complexities of downstream water quality considerations within the optimization formulation to determine operating strategies for a system of hydropower reservoirs operating in series (tandem) or parallel. The formulation was used to determine operating strategies for six reservoirs of the upper Cumberland river basin in Tennessee and Kentucky. Significant dissolved oxygen (DO) violations occur just upstream of Nashville, Tennessee below Old Hickory dam during the months of August and September. Daily reservoir releases were determined for the period of June through September which would produce the maximum hydropower revenue while meeting downstream water quality objectives. Optimal releases for three operational strategies were compared to historical operations for the years 1985, 1986, and 1988. These strategies included: spilling as necessary to meet water quality criteria, near normal operation (minimal spills), and drawdown of reservoirs as necessary to meet criteria without spills. Optimization results showed an 8% to 15% hydropower loss may be necessary to meet water quality criteria through spills and a 2% to 9% improvement in DO below Old Hickory may be possible without significant spills. Results also showed that substantial increases in initial headwater elevations would be necessary to meet daily DO criteria and avoid spills. The optimal control theory algorithm used to solve the problem proved to be an efficient and robust solver of this large optimization problem

Emotional stability components of human performance problems

International Nuclear Information System (INIS)

Wexler, R.H.

1987-01-01

Over half of all significant events that occur in nuclear plants involve human performance problems. There is increasing worldwide recognition that human performance problems have a significant impact on the safety, cost, and efficiency of nuclear plant operations. Emotional stability components have an important direct and indirect impact on human performance problems. This paper examines emotional stability components that are currently incorporated into human performance evaluation systems (HPES) in nuclear plants. It describes HPES programs being developed around the world, the emotional stability components that are currently referred to in these programs, and suggestions for improving HPES programs through a greater understanding of emotion stability components. A review of emotional stability components that may hinder or promote a plant environment that encourages the voluntary reporting and correction of human error is also presented

Improved quantum-inspired evolutionary algorithm with diversity information applied to economic dispatch problem with prohibited operating zones

International Nuclear Information System (INIS)

Vianna Neto, Julio Xavier; Andrade Bernert, Diego Luis de; Santos Coelho, Leandro dos

2011-01-01

The objective of the economic dispatch problem (EDP) of electric power generation, whose characteristics are complex and highly nonlinear, is to schedule the committed generating unit outputs so as to meet the required load demand at minimum operating cost while satisfying all unit and system equality and inequality constraints. Recently, as an alternative to the conventional mathematical approaches, modern meta-heuristic optimization techniques have been given much attention by many researchers due to their ability to find an almost global optimal solution in EDPs. Research on merging evolutionary computation and quantum computation has been started since late 1990. Inspired on the quantum computation, this paper presented an improved quantum-inspired evolutionary algorithm (IQEA) based on diversity information of population. A classical quantum-inspired evolutionary algorithm (QEA) and the IQEA were implemented and validated for a benchmark of EDP with 15 thermal generators with prohibited operating zones. From the results for the benchmark problem, it is observed that the proposed IQEA approach provides promising results when compared to various methods available in the literature.

Improved quantum-inspired evolutionary algorithm with diversity information applied to economic dispatch problem with prohibited operating zones

Energy Technology Data Exchange (ETDEWEB)

Vianna Neto, Julio Xavier, E-mail: julio.neto@onda.com.b [Pontifical Catholic University of Parana, PUCPR, Undergraduate Program at Mechatronics Engineering, Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil); Andrade Bernert, Diego Luis de, E-mail: dbernert@gmail.co [Pontifical Catholic University of Parana, PUCPR, Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil); Santos Coelho, Leandro dos, E-mail: leandro.coelho@pucpr.b [Pontifical Catholic University of Parana, PUCPR, Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil)

2011-01-15

The objective of the economic dispatch problem (EDP) of electric power generation, whose characteristics are complex and highly nonlinear, is to schedule the committed generating unit outputs so as to meet the required load demand at minimum operating cost while satisfying all unit and system equality and inequality constraints. Recently, as an alternative to the conventional mathematical approaches, modern meta-heuristic optimization techniques have been given much attention by many researchers due to their ability to find an almost global optimal solution in EDPs. Research on merging evolutionary computation and quantum computation has been started since late 1990. Inspired on the quantum computation, this paper presented an improved quantum-inspired evolutionary algorithm (IQEA) based on diversity information of population. A classical quantum-inspired evolutionary algorithm (QEA) and the IQEA were implemented and validated for a benchmark of EDP with 15 thermal generators with prohibited operating zones. From the results for the benchmark problem, it is observed that the proposed IQEA approach provides promising results when compared to various methods available in the literature.

Improved quantum-inspired evolutionary algorithm with diversity information applied to economic dispatch problem with prohibited operating zones

Energy Technology Data Exchange (ETDEWEB)

Neto, Julio Xavier Vianna [Pontifical Catholic University of Parana, PUCPR, Undergraduate Program at Mechatronics Engineering, Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil); Bernert, Diego Luis de Andrade; Coelho, Leandro dos Santos [Pontifical Catholic University of Parana, PUCPR, Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil)

2011-01-15

The objective of the economic dispatch problem (EDP) of electric power generation, whose characteristics are complex and highly nonlinear, is to schedule the committed generating unit outputs so as to meet the required load demand at minimum operating cost while satisfying all unit and system equality and inequality constraints. Recently, as an alternative to the conventional mathematical approaches, modern meta-heuristic optimization techniques have been given much attention by many researchers due to their ability to find an almost global optimal solution in EDPs. Research on merging evolutionary computation and quantum computation has been started since late 1990. Inspired on the quantum computation, this paper presented an improved quantum-inspired evolutionary algorithm (IQEA) based on diversity information of population. A classical quantum-inspired evolutionary algorithm (QEA) and the IQEA were implemented and validated for a benchmark of EDP with 15 thermal generators with prohibited operating zones. From the results for the benchmark problem, it is observed that the proposed IQEA approach provides promising results when compared to various methods available in the literature. (author)

Abortion: A significant problem of public health and a determinant of biological reproduction

OpenAIRE

Todorović Miodrag; Radovanović Olica

2006-01-01

Artificial abortion is a very important social-medical, economic and demographic problem. It is not only a problem of public health (disease disability, sterility) and social economy (to lose income and compensation because of absenteeism, increase of expense in health care sector for the treatment of direct, early and late consequences and sterility). It is a very important demographic problem because of the increase in "unrealized fertilities" and lost of descendents. According to the regis...

Evaluation of diagnostic and operative problems in basal meningioma by two-plane CT and angiography

International Nuclear Information System (INIS)

Inoue, Hiroshi; Tamura, Masaru; Kawafuchi, Jun-ichi

1982-01-01

Basal meningiomas were investigated using two-plane computed tomography (CT) with an ordinary section combined with a reverse section to ascertain the precise site of the origin, size, extension, properties and relation to adjacent tissue. Furthermore, with information obtained from angiography, operative difficulty and operative indications were investigated, to determine a therapeutic policy taking neurofunctional prognosis into consideration. The factors directly affecting the operative difficulty were the large size of the tumor, deformity of the hypothamus and brain stem, supratentorial or infratentorial extension, bone erosion, calcification of the tumor, direct effect on the major vessels and high vascularity. It is considered to be difficult or impossible to perform operations in cases accompanied by more than three of these factors and, in the case of posterior fossa tumors, more than two. Tumor density, extent of enhancement, perifocal low-density, ventricular dilatation, transtentorial herniation, brain or brain stem displacement, bone erosion on CT scans as well as tumor vascularity, feeding arteries, and changes in the major vessels on angiograms were also studied, and therapeutic problems as well as their countermeasures regarding these findings were discussed. It is emphasized that obtaining more accurate information concerning the preoperative state is the first step towards the improvement of therapeutic results in basal meningiomas. (author)

The IDA cognitive model for the analysis of nuclear power plant operator response under accident conditions. Part I: problem solving and decision making model

International Nuclear Information System (INIS)

Smidts, C.; Shen, S.H.; Mosleh, A.

1997-01-01

This paper is the first of a series of papers describing IDA which is a cognitive model for analysing the behaviour of nuclear power plant operators under accident conditions. The domain of applicability of the model is a relatively constrained environment where behaviour is significantly influenced by high levels of training and explicit requirement to follow written procedures. IDA consists of a model for individual operator behaviour and a model for control room operating crew expanded from the individual model. The model and its derivatives such as an error taxonomy and data collection approach has been designed with ultimate objective of becoming a quantitative method for human reliability analysis (HRA) in probabilistic risk assessment (PRA). The present paper gives a description of the main components of IDA such as memory structure, goals, and problem solving and decision making strategies. It also identifies factors that are at the origin of transitions between goals or between strategies. These factors cover the effects of external conditions and psychological state of the operator. The description is generic at first and then made specific to the nuclear power plant environment and more precisely to abnormal conditions

Fundamental Problems in the Operation of the Automotive Parts Industry Small and Medium Businesses in Bangkok and Surrounding Provinces

OpenAIRE

P. Thepnarintra

2015-01-01

The purposes of this study were to: 1) investigate operation conditions of SME automotive part industry in Bangkok and vicinity and 2) to compare operation problem levels of SME automotive part industry in Bangkok and vicinity according to the sizes of the enterprises. Samples in this study included 196 entrepreneurs of SME automotive part industry in Bangkok and vicinity derived from simple random sampling and calculation from R. V. Krejcie and D. W. Morgan's tables. Res...

Subcutaneous drug infusions: a review of problems and solutions.

Science.gov (United States)

Mitten, T

2001-02-01

Subcutaneous drug infusion using a portable syringe driver has had a significant impact on patient comfort in palliative care. It permits the continuous delivery of a range of drug therapies, so bypassing problems of dysphagia, weakness and the inability of many patients in the terminal phase to take oral medication. The devices are not problem-free, however. Mechanical problems, reactions at the infusion site and difficulties with the mixing of drugs in the syringe are all widely recognized. This article reviews some general issues with the operation of portable syringe drivers, and discusses a range of potential problems and their solutions.

Proceedings of the CSNI WGOE/SEGHOF workshop on modifications at nuclear power plants - Operating experience, safety significance and the role of human factors and organisation

International Nuclear Information System (INIS)

2004-01-01

Operating experience repeatedly shows that changes and modifications at nuclear power plants (NPPs) may lead to safety significant events. At the same time, modifications are necessary to ensure a safe and economic functioning of the NPPs. To ensure the continuing safety of NPPs it is important that processes for change and modification are given proper attention both by the NPPs and the regulators. The operability, maintainability and testability of every modification should be thoroughly assessed from different points of view to ensure that no safety problems are introduced. The OECD/NEA Committee on Safety of Nuclear Installations (CSNI) addressed the issue of modifications at a 'Workshop on Modifications at Nuclear Power Plants - Operating Experience, Safety Significance and Role of Human Factors' held at the OECD headquarters in Paris on October 6 to 8, 2003. This workshop was undertaken as a joint effort of the Working Group on Operating Experience (WGOE) and the Special Experts Group on Human and Organisational Factors (SEGHOF). During the workshop, WGOE focused on the theme of 'Minor Modifications and their Safety Significance', while SEGHOF focused on the topic 'Human and Organisational Factors in NPP Modifications'. The workshop was attended by 55 experts from the industry, regulators and technical support organizations in 15 countries. The workshop programme consisted of plenary and parallel sessions for presentations and discussions. One important part of the workshop was to discuss findings of the WGOE and SEGHOF surveys of utility and regulatory experience from modifications at the NPPs. Modifications at the NPPs are controlled by written procedures. The process varies depending on the type of the modification. Large modifications generally lead to fewer problems, because the projects are given both a great deal of attention and resources. In contrast, minor modifications seem to represent a generic challenge because they are less likely to be

Significant factors for work attractiveness and how these differ from the current work situation among operating department nurses.

Science.gov (United States)

Björn, Catrine; Lindberg, Magnus; Rissén, Dag

2016-01-01

The aim was to examine significant factors for work attractiveness and how these differ from the current work situation among operating department nurses. A second objective was to examine the associations between age, gender, length of employment, work engagement, work ability, self-rated health indicators and attractiveness of the current work situation. The attractiveness of work is rarely taken into account in research on nurse retention. To expand this knowledge, it is relevant to examine factors that make work attractive and their associations with related concepts. Correlational, cross-sectional survey using a convenience sample. Questionnaires were answered by 147 nurses in four operating departments in Sweden. Correlation and regression analyses were conducted. The nurses rated the significance of all factors of work attractiveness higher than they rated those factors in their current work situation; salary, organisation and physical work environment had the largest differences. The most significant attractive factors were relationships, leadership and status. A statistically significant positive correlation between work engagement and attractive work was found. In the multiple regression model, the independent variables work engagement and older age significantly predicted work attractiveness. Several factors should be considered in the effort to increase work attractiveness in operating departments and thereby to encourage nurse retention. Positive aspects of work seem to unite work engagement and attractive work, while work ability and self-rated health indicators are other important dimensions in nurse retention. The great discrepancies between the significance of attractive factors and the current work situation in salary, organisation and physical work environment suggest ways in which work attractiveness may be increased. To discover exactly what needs to be improved may require a deeper look into the construct of the examined factors. © 2015 John

Solvability conditions of the Cauchy problem for two-dimensional systems of linear functional differential equations with monotone operators

Czech Academy of Sciences Publication Activity Database

Šremr, Jiří

2007-01-01

Roč. 132, č. 3 (2007), s. 263-295 ISSN 0862-7959 R&D Projects: GA ČR GP201/04/P183 Institutional research plan: CEZ:AV0Z10190503 Keywords : system of functional differential equations with monotone operators * initial value problem * unique solvability Subject RIV: BA - General Mathematics

Genetic Algorithms for Multiple-Choice Problems

Science.gov (United States)

Aickelin, Uwe

2010-04-01

This thesis investigates the use of problem-specific knowledge to enhance a genetic algorithm approach to multiple-choice optimisation problems.It shows that such information can significantly enhance performance, but that the choice of information and the way it is included are important factors for success.Two multiple-choice problems are considered.The first is constructing a feasible nurse roster that considers as many requests as possible.In the second problem, shops are allocated to locations in a mall subject to constraints and maximising the overall income.Genetic algorithms are chosen for their well-known robustness and ability to solve large and complex discrete optimisation problems.However, a survey of the literature reveals room for further research into generic ways to include constraints into a genetic algorithm framework.Hence, the main theme of this work is to balance feasibility and cost of solutions.In particular, co-operative co-evolution with hierarchical sub-populations, problem structure exploiting repair schemes and indirect genetic algorithms with self-adjusting decoder functions are identified as promising approaches.The research starts by applying standard genetic algorithms to the problems and explaining the failure of such approaches due to epistasis.To overcome this, problem-specific information is added in a variety of ways, some of which are designed to increase the number of feasible solutions found whilst others are intended to improve the quality of such solutions.As well as a theoretical discussion as to the underlying reasons for using each operator,extensive computational experiments are carried out on a variety of data.These show that the indirect approach relies less on problem structure and hence is easier to implement and superior in solution quality.

Safety significance of component ageing, exemplary for MOV, based on French and German operating experience

Energy Technology Data Exchange (ETDEWEB)

Morlent, O. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Michel, F. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching (Germany)

2001-07-01

An outline is given of how IPSN and GRS assess the effects of physical ageing on the safety of French and German Nuclear Power Plants (NPPs) on the basis of the available knowledge and how investigations are carried out. The presentation is focused exemplary on a preliminary study illustrating approaches for the evaluation of the ageing behaviour of active components, the motor-operated valves (MOV). The results so far seems to demonstrate that the developed methodological approaches are suitable to obtain qualitative evidence with regard to the ageing behaviour of technical facilities such as MOV. The evaluation of the operating experience with French 900 MWe plants seems to reveal, for MOV of one system, a trend similar to some international findings about ageing-related events with increasing operating time; this trend will have to be confirmed. For the German NPPs so far, there appears to be no significant increase of ageing-related events concerning MOV as the plants get older. Future work on ageing scheduled at IPSN and GRS includes further cooperation on this issue, too; a deep analysis is necessary to explain the reasons of such apparent differences before any conclusion. (authors)

Safety significance of component ageing, exemplary for MOV, based on French and German operating experience

International Nuclear Information System (INIS)

Morlent, O.

2001-01-01

An outline is given of how IPSN and GRS assess the effects of physical ageing on the safety of French and German Nuclear Power Plants (NPPs) on the basis of the available knowledge and how investigations are carried out. The presentation is focused exemplary on a preliminary study illustrating approaches for the evaluation of the ageing behaviour of active components, the motor-operated valves (MOV). The results so far seems to demonstrate that the developed methodological approaches are suitable to obtain qualitative evidence with regard to the ageing behaviour of technical facilities such as MOV. The evaluation of the operating experience with French 900 MWe plants seems to reveal, for MOV of one system, a trend similar to some international findings about ageing-related events with increasing operating time; this trend will have to be confirmed. For the German NPPs so far, there appears to be no significant increase of ageing-related events concerning MOV as the plants get older. Future work on ageing scheduled at IPSN and GRS includes further cooperation on this issue, too; a deep analysis is necessary to explain the reasons of such apparent differences before any conclusion. (authors)

The moment problem

CERN Document Server

Schmüdgen, Konrad

2017-01-01

This advanced textbook provides a comprehensive and unified account of the moment problem. It covers the classical one-dimensional theory and its multidimensional generalization, including modern methods and recent developments. In both the one-dimensional and multidimensional cases, the full and truncated moment problems are carefully treated separately. Fundamental concepts, results and methods are developed in detail and accompanied by numerous examples and exercises. Particular attention is given to powerful modern techniques such as real algebraic geometry and Hilbert space operators. A wide range of important aspects are covered, including the Nevanlinna parametrization for indeterminate moment problems, canonical and principal measures for truncated moment problems, the interplay between Positivstellensätze and moment problems on semi-algebraic sets, the fibre theorem, multidimensional determinacy theory, operator-theoretic approaches, and the existence theory and important special topics of multidime...

XY vs X Mixer in Quantum Alternating Operator Ansatz for Optimization Problems with Constraints

Science.gov (United States)

Wang, Zhihui; Rubin, Nicholas; Rieffel, Eleanor G.

2018-01-01

Quantum Approximate Optimization Algorithm, further generalized as Quantum Alternating Operator Ansatz (QAOA), is a family of algorithms for combinatorial optimization problems. It is a leading candidate to run on emerging universal quantum computers to gain insight into quantum heuristics. In constrained optimization, penalties are often introduced so that the ground state of the cost Hamiltonian encodes the solution (a standard practice in quantum annealing). An alternative is to choose a mixing Hamiltonian such that the constraint corresponds to a constant of motion and the quantum evolution stays in the feasible subspace. Better performance of the algorithm is speculated due to a much smaller search space. We consider problems with a constant Hamming weight as the constraint. We also compare different methods of generating the generalized W-state, which serves as a natural initial state for the Hamming-weight constraint. Using graph-coloring as an example, we compare the performance of using XY model as a mixer that preserves the Hamming weight with the performance of adding a penalty term in the cost Hamiltonian.

The role and significance marketing in modern business operation

OpenAIRE

Simonović, Zoran; Miletić, Slavomir; Miletić, Vuk

2012-01-01

Marketing is a science that deals with the market, market needs and the ways of meeting these needs. Marketing, as a business philosophy of intensive production, is focused on analyzing and noticing all the problems referring to the distribution and selling of the goods from the producer to the consumer. This field is constantly developing together with market expansion and its goal is to set the theoretical background for the market business strategies. In marketing theory, the market succes...

Evaluating operator performance on full-scope simulators: A pragmatic approach to an intractable measurement problem

International Nuclear Information System (INIS)

Fuld, R.

1989-01-01

Industry trends toward full-scope, plant-referenced control room simulators have accelerated. The cost of such training is high, but the cost of training ineffectiveness is even higher if it permits serious errors or operator disqualification to occur. Effective measures of operator performance are needed, but the complexity of the task environment and the many aspects of and requirements for operator performance conspire to make such measurement a challenging problem. Combustion Engineering (C-E) Owners' Group task No. 572 was undertaken to develop a tractable and effective methodology for evaluating team performance in a requalification context on full-scope simulator scenarios. The following concepts were pursued as design goals for the method: 1. validity; 2. sensitivity; 3. reliability; 4. usability. In addition, the resulting approach was to meet the requirements of ES-601, Implementation Guidance of the NRC for Administration of Requalifying Exams. A survey of existing evaluation tools and techniques was made to determine the strengths and weaknesses of each. Based on those findings, a multimethod approach was developed drawing on the combined strengths of several general methods. The paper discusses procedural milestones, comments as subjective ratings, failure criteria, and tracked plant parameters

Diffraction and Dirchlet problem for parameter-elliptic convolution ...

African Journals Online (AJOL)

In this paper we evaluate the difference between the inverse operators of a Dirichlet problem and of a diffraction problem for parameter-elliptic convolution operators with constant symbols. We prove that the inverse operator of a Dirichlet problem can be obtained as a limit case of such a diffraction problem. Quaestiones ...

[The social hygiene problems in the operator work of hydroelectric power station workers and the means for enhancing work capacity].

Science.gov (United States)

Karakashian, A N; Lepeshkina, T R; Ratushnaia, A N; Glushchenko, S S; Zakharenko, M I; Lastovchenko, V B; Diordichuk, T I

1993-01-01

Weight, tension and harmfulness of professional activity, peculiarities of labour conditions and characteristics of work, shift dynamics of operative personnel's working capacity were studied in the course of 8-hour working day currently accepted at hydroelectric power stations (HEPS) and experimental 12-hour schedule. Working conditions classified as "admissible", positive dynamics of operators' state, their social and material contentment were a basis for 12-hour two-shift schedule to be recommended as more appropriate. At the same time, problem of optimal shift schedules for operative personnel of HEPS remains unsolved and needs to be further explored.

NORMALIZATION OF AUTOMOTIVE BRAKE CHARACTERISTICS WHILE OPERATING THEM IN THE REPUBLIC OF BELARUS

Directory of Open Access Journals (Sweden)

I. M. Flerko

2012-01-01

Full Text Available Safety provision for the operated auto-transport facilities is of great significance all over the world. The problem is also considered as an actual one for the automotive transport of theRepublicofBelarus. Provision of higher brake system reliability for the operated vehicles is one of the directions to solve the problem pertaining to improve traffic safety.The paper contains an analysis of basic national standard documents which regulate brake characteristics for the operated vehicles, evaluates checking methods of braking efficiency and vehicle stability at the moment of braking, considers some problems pertaining to methods used for checking and estimation of braking control systems of transport facilities. 

Application of an engineering problem-solving methodology to address persistent problems in patient safety: a case study on retained surgical sponges after surgery.

Science.gov (United States)

Anderson, Devon E; Watts, Bradley V

2013-09-01

Despite innumerable attempts to eliminate the postoperative retention of surgical sponges, the medical error persists in operating rooms worldwide and places significant burden on patient safety, quality of care, financial resources, and hospital/physician reputation. The failure of countless solutions, from new sponge counting methods to radio labeled sponges, to truly eliminate the event in the operating room requires that the emerging field of health-care delivery science find innovative ways to approach the problem. Accordingly, the VA National Center for Patient Safety formed a unique collaboration with a team at the Thayer School of Engineering at Dartmouth College to evaluate the retention of surgical sponges after surgery and find a solution. The team used an engineering problem solving methodology to develop the best solution. To make the operating room a safe environment for patients, the team identified a need to make the sponge itself safe for use as opposed to resolving the relatively innocuous counting methods. In evaluation of this case study, the need for systematic engineering evaluation to resolve problems in health-care delivery becomes clear.

Clinical significance of measurement of changes serum SE-CAD, CEA and CA19-9 contents after operation in patients with gastric cancer

International Nuclear Information System (INIS)

Jin Wentao; Jin Zeqiu; Jiang Hui

2007-01-01

Objective: To explore the clinical significance of changes of serum SE-CAD, CEA and CA19-9 levels in patients with gastric cancer after operation. Methods: Serum levels of soluble E-Cadherin were measured with ELISA and serum CEA, CA19 -9 levels measared with RIA in 32 patients with gastric cancer both before and 6 months after operation as well as in 30 controls. Results: Serum SE-CAD, CEA and CA19-9 levels were significantly higher in the patients than those in the controls before operation (P 0.05). Conclusion: Changes of serum SE-CAD, CEA and CA19-9 levels after operation might be prognostic importance in patients with gastric cancer. (authors)

On the completeness of systems of eigenfunctions of the Sturm-Liouville operator with a potential depending on the spectral parameter and a nonlinear problem

International Nuclear Information System (INIS)

Zhidkov, P.E.

1996-01-01

First, the eigenvalue problem on the segment [0,1] for the Sturm-Liouville operator with a potential depending on the spectral parameter with the zero Dirichlet boundary conditions is considered. For this problem, under some hypotheses on the potential, it is proved that the necessary and sufficient condition for an arbitrary system of eigenfunctions, possessing a unique function with n roots in the interval (0,1) for an arbitrary non-negative integer number n, being complete in the space L 2 (0,1) is the linear independence of the functions from this system in the space L 2 (0,1). Then, this result is applied to the investigation of an eigenvalue problem for a nonlinear operator on the Sturm-Liouville type. For this problem, the completeness of the system of its eigenfunctions in the space L 2 (0,1) is proved. (author). 12 refs

RISK DECREASE PROBLEM WITH MAKING ERRORS IN ACTIVITY OF OPERATORS DEALING WITH AUTOMATIC CONTROL SYSTEMS OF GAS-DISTRIBUTION STATIONS

Directory of Open Access Journals (Sweden)

V. V. Egorov

2011-01-01

Full Text Available The paper contains an analysis of specific features pertaining to the activity of operators dealing with automatic control systems of gas-distribution stations. The professional operator’s activity is presented in the form of the developed data model. Possible conceptual approaches to the research are analyzed in the paper. The paper describes an author’s approach to studying a risk decrease problem in the activity of operators on the basis of the analytical research results. Technology for obtaining  research results is cited in the paper. 

Design retrofit to prevent damage due to heat transport pump operation under conditions of significant void

Energy Technology Data Exchange (ETDEWEB)

Lam, K F [Bruce Engineering Department, In-Service Nuclear Projects, Ontario Hydro, North York, ON (Canada)

1991-04-01

The purpose of this paper is to provide a general review of certain key design areas which address the safety concerns of HT pump operation under conditions of significant void. To illustrate the challenges confronting designers and analysts, some of the highlights during the design of a protective system to prevent damage to HT piping and pump supports at Bruce NGS 'A' are outlined. The effects of this protective system on reactor safety are also discussed. HI pump operation under conditions of significant void offers a major challenge to designers and analysts to ensure that pump induced vibration and its effects on pump and piping are addressed. For an in-service station the search for a practical solution is often limited by existing. station equipment design and Layout. The diversity of design verification process requires a major commitment of engineering resources to ensure all. safety aspects meet the requirements of regulatory body. Work currently undertaken at Ontario Hydro Research Pump Test Complex on two-phase flow in pumps and piping may provide better prediction of vibration characteristics so that inherent conservativeness in fatigue Life prediction of HI system components can be reduced.

Design retrofit to prevent damage due to heat transport pump operation under conditions of significant void

International Nuclear Information System (INIS)

Lam, K.F.

1991-01-01

The purpose of this paper is to provide a general review of certain key design areas which address the safety concerns of HT pump operation under conditions of significant void. To illustrate the challenges confronting designers and analysts, some of the highlights during the design of a protective system to prevent damage to HT piping and pump supports at Bruce NGS 'A' are outlined. The effects of this protective system on reactor safety are also discussed. HI pump operation under conditions of significant void offers a major challenge to designers and analysts to ensure that pump induced vibration and its effects on pump and piping are addressed. For an in-service station the search for a practical solution is often limited by existing. station equipment design and Layout. The diversity of design verification process requires a major commitment of engineering resources to ensure all. safety aspects meet the requirements of regulatory body. Work currently undertaken at Ontario Hydro Research Pump Test Complex on two-phase flow in pumps and piping may provide better prediction of vibration characteristics so that inherent conservativeness in fatigue Life prediction of HI system components can be reduced

Operational Optimization in Port Container Terminals

DEFF Research Database (Denmark)

As a result of the significant increase in worldwide containerized transportation the development of efficient handling systems in marine terminals has become very important for port competitiveness. In order to optimize the productivity the total handling time for containers in the terminal must...... be minimized. An overview of the different operational problems in port container terminals is presented and an aggregated model and solution approach is shown. Next, there will be focused on the yard storage problem and a mathematical formulation and solution proposals will be presented....

Clinical significance of determination of changes of serum CA153, CA125 and TSGF levels after operation in patients with breast cancer

International Nuclear Information System (INIS)

Zhou Jun; Wang Zhaoxin; Wang Yan; Wang Rui

2007-01-01

Objective: To study the clinical significance of changes serum CA153, CA125 and TSGF levels after operation in patients with breast cancer. Methods: Serum CA153, CA125 and TSGF (with RIA) and serum TSGF levels (with biochemistry method) were measured in 36 patients with breast cancer both before and after operation as well as in 35 controls. Results: Before operation, serum levels of serum CA153, CA125 and TSGF in the patients were significantly higher than those in the controls (P < 0.01 ). One month after operation, all the levels were approaching normal. Six months later, the levels in the patients without recurrence remained normal, however, the levels in the 4 patients with recurrence returned to those before operation again. Conclusion: Changes of serum CA153, CA125 and TSGF levels are closely related to the tumor burden and if levels were high after operation, may indicate the presence of recurrence. (authors)

An approach toward estimating the safety significance of normal and abnormal operating procedures in nuclear power plants

International Nuclear Information System (INIS)

Grant, T.F.; Harris, M.S.

1989-01-01

The Nuclear Regulatory Commission's TMI Action Plan calls for a long-term plan to upgrade operating procedures in nuclear power plants. The scope of Generic Issue Human Factors 4.4, which stems from this requirement, includes the recommendation of improvements in nuclear power plant normal and abnormal operating procedures (NOPs and AOPs) and the implementation of appropriate regulatory action. This paper will describe the objectives, methodologies, and results of a Battelle-conducted value impact assessment to determine the costs and benefits of having the NRC implement regulatory action that would specify requirements for the preparation of acceptable NOPs and AOPs by the Commission's nuclear power plant licensees. The results of this value impact assessment are expressed in terms of ten cost/benefit attributes that can be affected by the NRC regulatory action. Five of these attributes require the calculation of change in public risk that could be expected to result from the action which, in this case, required determining the safety significance of NOPs and AOPs. In order to estimate this safety significance, a multi-step methodology was created that relies on an existing Probabilistic Risk Assessment (PRA) to provide a quantitative framework for modeling the role of operating procedures. The purpose of this methodology is to determine what impact the improvement of NOPs and AOPs would have on public health and safety

Generalized bi-quasi-variational inequalities for quasi-semi-monotone and bi-quasi-semi-monotone operators with applications in non-compact settings and minimization problems

Directory of Open Access Journals (Sweden)

Chowdhury Molhammad SR

2000-01-01

Full Text Available Results are obtained on existence theorems of generalized bi-quasi-variational inequalities for quasi-semi-monotone and bi-quasi-semi-monotone operators in both compact and non-compact settings. We shall use the concept of escaping sequences introduced by Border (Fixed Point Theorem with Applications to Economics and Game Theory, Cambridge University Press, Cambridge, 1985 to obtain results in non-compact settings. Existence theorems on non-compact generalized bi-complementarity problems for quasi-semi-monotone and bi-quasi-semi-monotone operators are also obtained. Moreover, as applications of some results of this paper on generalized bi-quasi-variational inequalities, we shall obtain existence of solutions for some kind of minimization problems with quasi- semi-monotone and bi-quasi-semi-monotone operators.

Operational problems associated with the use of particulate emission control for MACT compliance applications

International Nuclear Information System (INIS)

Compton, J.A.

1992-03-01

Tests of high-efficiency particulate air filters were requested following catastrophic failure of a filter by hydrogen fluoride gas from improper operation in a production line. Operational lives in hydrogen fluoride environments of high-efficiency particulate air filters were determined in statistically designed experiments for three variable. The variables studied were hydrogen fluoride gas concentration, water vapor concentration, and wind speed through a hydrogen fluoride-resistant filter medium. The program was terminated after 11 of the 16 runs were completed. The 11 runs indicate no statistically significant effect by any of the three variables. Two additional runs were completed with non-hydrogen fluoride-resistant filters and shorter operating lives were found. The tests determined that the interim operational safety limits imposed after the original filter failure were adequate. More frequent testing of the filters in the associated production line was recommended for assuring filter integrity. The tests also showed that filter efficiency loss is relatively slow at first, but accelerates

A short-term operating room surgery scheduling problem integrating multiple nurses roster constraints.

Science.gov (United States)

Xiang, Wei; Yin, Jiao; Lim, Gino

2015-02-01

Operating room (OR) surgery scheduling determines the individual surgery's operation start time and assigns the required resources to each surgery over a schedule period, considering several constraints related to a complete surgery flow and the multiple resources involved. This task plays a decisive role in providing timely treatments for the patients while balancing hospital resource utilization. The originality of the present study is to integrate the surgery scheduling problem with real-life nurse roster constraints such as their role, specialty, qualification and availability. This article proposes a mathematical model and an ant colony optimization (ACO) approach to efficiently solve such surgery scheduling problems. A modified ACO algorithm with a two-level ant graph model is developed to solve such combinatorial optimization problems because of its computational complexity. The outer ant graph represents surgeries, while the inner graph is a dynamic resource graph. Three types of pheromones, i.e. sequence-related, surgery-related, and resource-related pheromone, fitting for a two-level model are defined. The iteration-best and feasible update strategy and local pheromone update rules are adopted to emphasize the information related to the good solution in makespan, and the balanced utilization of resources as well. The performance of the proposed ACO algorithm is then evaluated using the test cases from (1) the published literature data with complete nurse roster constraints, and 2) the real data collected from a hospital in China. The scheduling results using the proposed ACO approach are compared with the test case from both the literature and the real life hospital scheduling. Comparison results with the literature shows that the proposed ACO approach has (1) an 1.5-h reduction in end time; (2) a reduction in variation of resources' working time, i.e. 25% for ORs, 50% for nurses in shift 1 and 86% for nurses in shift 2; (3) an 0.25h reduction in

New technologies - new corrosion problems

International Nuclear Information System (INIS)

Heitz, E.

1994-01-01

Adequate resistance of materials to corrosion is equally important for classical and for new technologies. This article considers the economic consequences of corrosion damage and, in addition to the long-known GNP orientation, presents a new approach to the estimation of the costs of corrosion and corrosion protection via maintenance and especially corrosion-related maintenance. The significance of ''high-tech'', ''medium-tech'' and ''low-tech'' material and corrosion problems is assessed. Selected examples taken from new technologies in the areas of power engineering, environmental engineering, chemical engineering, and biotechnology demonstrate the great significance of the problems. It is concluded that corrosion research and corrosion prevention technology will never come to an end but will constantly face new problems. Two technologies are of particular interest since they focus attention on new methods of investigation: microelectronics and final disposal of radioactive wastes. The article closes by considering the importance of the transfer of experience and technology. Since the manufacturs and operators of machines and plant do not generally have access to the very latest knowledge, they should be kept informed through advisory services, experimental studies, databases, and further education. (orig.) [de

Safety problems in fuel reprocessing plants

International Nuclear Information System (INIS)

Amaury, P.; Jouannaud, C.; Niezborala, F.

1979-01-01

The document first situates the reprocessing in the fuel cycle as a whole. It shows that a large reprocessing plant serves a significant number of reactors (50 for a plant of 1500 tonnes per annum). It then assesses the potential risks with respect to the environment as well as with respect to the operating personnel. The amounts of radioactive matter handled are very significant and their easily dispersible physical form represents very important risks. But the low potential energy likely to bring about this dispersion and the very severe and plentiful confinement arrangements are such that the radioactive risks are very small, both with respect to the environment and the operating personnel. The problems of the interventions for maintenance or repairs are mentioned. The intervention techniques in a radioactive environment are perfected, but they represent the main causes of operating personnel irradiation. The design principle applied in the new plants take this fact into account, involving a very significant effort to improve the reliability of the equipment and ensuring the provision of devices enabling the failing components to be replaced without causing irradiation of the personnel [fr

Quayside Operations Planning Under Uncertainty

DEFF Research Database (Denmark)

Iris, Cagatay; Jin, Jian Gang; Lee, Der-Hong

The quayside operation problem is one of the key components in the management system for a container terminal. This work focuses on three important problems that represent a bottleneck on terminal operations: Berth Allocation Problem (BAP), Quay Crane Assignment and Scheduling Problems (QCASP......).The state-of-art models mostly rely on forecasted, deterministic vessel arrivals, and they mostly assume that uniform QC operations is maintained. However, in reality, these parameters are mostly random. In this study, we present a stochastic programming approach based on a decomposition algorithm to solve...

Cross-national differences in clinically significant cannabis problems: epidemiologic evidence from 'cannabis-only' smokers in the United States, Mexico, and Colombia

Directory of Open Access Journals (Sweden)

Posada-Villa Jose

2010-03-01

Full Text Available Abstract Background Epidemiological studies show wide variability in the occurrence of cannabis smoking and related disorders across countries. This study aims to estimate cross-national variation in cannabis users' experience of clinically significant cannabis-related problems in three countries of the Americas, with a focus on cannabis users who may have tried alcohol or tobacco, but who have not used cocaine, heroin, LSD, or other internationally regulated drugs. Methods Data are from the World Mental Health Surveys Initiative and the National Latino and Asian American Study, with probability samples in Mexico (n = 4426, Colombia (n = 5,782 and the United States (USA; n = 8,228. The samples included 212 'cannabis only' users in Mexico, 260 in Colombia and 1,724 in the USA. Conditional GLM with GEE and 'exact' methods were used to estimate variation in the occurrence of clinically significant problems in cannabis only (CO users across these surveyed populations. Results The experience of cannabis-related problems was quite infrequent among CO users in these countries, with weighted frequencies ranging from 1% to 5% across survey populations, and with no appreciable cross-national variation in general. CO users in Colombia proved to be an exception. As compared to CO users in the USA, the Colombia smokers were more likely to have experienced cannabis-associated 'social problems' (odds ratio, OR = 3.0; 95% CI = 1.4, 6.3; p = 0.004 and 'legal problems' (OR = 9.7; 95% CI = 2.7, 35.2; p = 0.001. Conclusions This study's most remarkable finding may be the similarity in occurrence of cannabis-related problems in this cross-national comparison within the Americas. Wide cross-national variations in estimated population-level cumulative incidence of cannabis use disorders may be traced to large differences in cannabis smoking prevalence, rather than qualitative differences in cannabis experiences. More research is needed to identify conditions that

Cyclic operation of power plant; Cyklisk drift av kraftvaermeverk

Energy Technology Data Exchange (ETDEWEB)

Storesund, Jan

2007-12-15

The great majority of power plants are designed for base load operation with a relatively small number of starts and stops per year. Therefore, there has been no need to consider fatigue at design. Over the last few years operation with more frequent starts and stops exists as a consequence of swinging electricity prices that has become common. This involves significantly higher frequency of damages; not least fatigue relates damages, and the number of severe failures in components that never before have had damage problems may increase as well. In the present work the different types of component that may suffer from cyclic operation related damage are gathered by a literature survey and described as follows: - where and how the damages comes up, - constructions that should be avoided, - non-destructive testing (NDT) for damage that may come up under cyclic operation, - calculation and assessment of integrity of critical components - areas where continued research would be valuable. Recommendations have been put together to be used to prevent cyclic operation related damage and to detect it in time. The target group for this study is i) plant owners of plants where cyclic operation is or may be present, ii) researchers in the area, and, iii) inspectors and NDT-operators. There are quite a number of components where cyclic operation has been found to significantly influence the lift time. Some of these components are described in many papers whereas occasional papers have been found for others. The amount of information that is possible to get for a certain component is likely related to its significance for cyclic operation damage. The most frequently reported problem is ligament cracking of high temperature headers. Other components where extensive studies have been done are: wall panels, creep-fatigue loaded welds and turbine components

Operational Plan Ontology Model for Interconnection and Interoperability

Science.gov (United States)

Long, F.; Sun, Y. K.; Shi, H. Q.

2017-03-01

Aiming at the assistant decision-making system’s bottleneck of processing the operational plan data and information, this paper starts from the analysis of the problem of traditional expression and the technical advantage of ontology, and then it defines the elements of the operational plan ontology model and determines the basis of construction. Later, it builds up a semi-knowledge-level operational plan ontology model. Finally, it probes into the operational plan expression based on the operational plan ontology model and the usage of the application software. Thus, this paper has the theoretical significance and application value in the improvement of interconnection and interoperability of the operational plan among assistant decision-making systems.

Industry Operating Experience Process at Krsko NPP

International Nuclear Information System (INIS)

Bach, B.; Bozin, B.; Cizmek, R.

2012-01-01

Experience has shown that number of minor events and near misses, usually without immediate or significant impact to plant safety and reliability, are precursors of significant or severe events due to the same or similar root or apparent cause(s). It is therefore desirable to identify and analyze weaknesses of the precursor problems (events) in order to prevent occurrence of significant events. Theoretically, significant events could be prevented from occurring if the root cause(s) of these precursor problems could be identified and eliminated. The Operating Experience Program identifies such event precursors and by reporting them to the industry, plant specific corrective actions can be taken to prevent events at other operational plants. The intent of the Operating Experience Program is therefore to improve nuclear power plant safety and reliability of the operating nuclear power plants. Each plant develops its own Operating Experience Program in order to learn from the in-house operating experience as well as from the world community of nuclear plants. The effective use of operating experience includes analyzing both plant and industry events in order to identify fundamental weaknesses and then determining appropriate plant-specific actions that will minimize the likelihood of similar events. Learning and applying the lessons from operating experience is an integral part of station safety culture and is encouraged by managers throughout the top plant administrative programs and procedures. Krsko NPP is developed it own Operating Experience Program by using the most relevant INPO/WANO/IAEA guidelines as well as its own knowledge, skills an operating practice. The Operating Experience Program is a part of the Corrective Action Program, which is among top management programs, thus program is strongly encouraged by top management. The purpose of Operating Experience Program is to provide guidance for using, sharing, and evaluating operating experience information

Clinical significance of changes of serum of P-selectin, CEA and TSGF levels after operation in patients with rectal cancer

International Nuclear Information System (INIS)

Wang Zhizhong; Huang Jin

2007-01-01

Objective: To study the clinical significance of postoperative changes of serum P-selectin, CEA and TSGF levels in patients with rectal cancer. Methods: Serum CEA (with RIA), P-selectin (with ELISA), and TSGF (with biochemistry levels were determined) in 32 patients with rectal cancer both before and after operation as well as in 30 controls. Results: Before operation, the serum P-selectin, CEA and TSGF levels were significantly higher than those in controls (P < 0.01), Twenty -two of the 30 patients underwent operative therapy showed no sign of recurrence at one year and their serum P-selectin, CEA and TSGF levels dropped to within normal range. Hower in the 8 patients with recurrence, the serum levels of P-selectin, CEA and TSGF remained abnormally high. Conclusion: Serum P-selectin, CEA and TSGF levels were closely related to the diseases process of rectal cancer and were of prognostic values. (authors)

Efficiency and Robustness in Railway Operations

DEFF Research Database (Denmark)

Bull, Simon Henry; Pisinger, David

reliability. Offering these services presents a challenging sequence of planning problems for operators. These range from problems considered on a daily basis to planning for years in the future, with different problems interacting and influencing each other. Operations research methods can be used...... to effectively model, investigate, and solve railway planning problems. Despite advances in computational power these large problems are still challenging to solve, especially as more modelling detail is sought. Within a Danish context this thesis seeks to apply operations research methods to different planning...... problems beyond past approaches, and where applicable, investigate solution methods that place more focus on the passenger and passenger experience. To cater to the growing demand for rail transport, and compete with different modes of transport, Danish railway operators must offer a consistent, reliable...

Physics-based models for measurement correlations: application to an inverse Sturm–Liouville problem

International Nuclear Information System (INIS)

Bal, Guillaume; Ren Kui

2009-01-01

In many inverse problems, the measurement operator, which maps objects of interest to available measurements, is a smoothing (regularizing) operator. Its inverse is therefore unbounded and as a consequence, only the low-frequency component of the object of interest is accessible from inevitably noisy measurements. In many inverse problems however, the neglected high-frequency component may significantly affect the measured data. Using simple scaling arguments, we characterize the influence of the high-frequency component. We then consider situations where the correlation function of such an influence may be estimated by asymptotic expansions, for instance as a random corrector in homogenization theory. This allows us to consistently eliminate the high-frequency component and derive a closed form, more accurate, inverse problem for the low-frequency component of the object of interest. We present the asymptotic expression of the correlation matrix of the eigenvalues in a Sturm–Liouville problem with unknown potential. We propose an iterative algorithm for the reconstruction of the potential from knowledge of the eigenvalues and show that using the approximate correlation matrix significantly improves the reconstructions

The economic and social significance of RCA regional co-operative projects

International Nuclear Information System (INIS)

Fowler, E.E.

1979-01-01

The regional Co-operative Agreement for Research, Development and Training Related to Nuclear Science and Technology (RCA) is an established and valuable instrument between the International Atomic Energy Agency (IAEA) and Member States in South Asia, Southeast Asia and the Pacific or Far East for assisting in the transfer of modern technology to areas having economic and social importance to the region. The purpose of this review is to identify on-going or planned work which is designed to help achieve this goal. Currently approved RCA Regional Co-operative Research Projects are listed

Cognitive Skills Used to Solve Mathematical Word Problems and Numerical Operations: A Study of 6- to 7-Year-Old Children

Science.gov (United States)

Bjork, Isabel Maria; Bowyer-Crane, Claudine

2013-01-01

This study investigates the relationship between skills that underpin mathematical word problems and those that underpin numerical operations, such as addition, subtraction, division and multiplication. Sixty children aged 6-7 years were tested on measures of mathematical ability, reading accuracy, reading comprehension, verbal intelligence and…

Compacted spent-fuel storage--designs and problems

International Nuclear Information System (INIS)

Rubinstein, H.J.; Gilcrest, J.D.; Kendall, W.R.

1979-01-01

Typical rack designs, licensing, contracting methods, installation and operational problems are described. Due to the lack of reprocessing and independent fuel storage facilities, new plants built in the United States will continue to install high-density spent-fuel storage racks. As to the rack designs, the most significant feature is the introduction of freestanding rack designs. The trends in spent-fuel storage appear to be toward the use of high-density racks, either with or without absorber, for all plants in the design, construction, or operation phase; the use of freestanding rack designs; and the separation of engineering and fabrication during procurement

Utility systems operation: Optimisation-based decision making

International Nuclear Information System (INIS)

Velasco-Garcia, Patricia; Varbanov, Petar Sabev; Arellano-Garcia, Harvey; Wozny, Guenter

2011-01-01

Utility systems provide heat and power to industrial sites. The importance of operating these systems in an optimal way has increased significantly due to the unstable and in the long term rising prices of fossil fuels as well as the need for reducing the greenhouse gas emissions. This paper presents an analysis of the problem for supporting operator decision making under conditions of variable steam demands from the production processes on an industrial site. An optimisation model has been developed, where besides for running the utility system, also the costs associated with starting-up the operating units have been modelled. The illustrative case study shows that accounting for the shut-downs and start-ups of utility operating units can bring significant cost savings. - Highlights: → Optimisation methodology for decision making on running utility systems. → Accounting for varying steam demands. → Optimal operating specifications when a demand change occurs. → Operating costs include start-up costs of boilers and other units. → Validated on a real-life case study. Up to 20% cost savings are possible.

Sorting signed permutations by short operations.

Science.gov (United States)

Galvão, Gustavo Rodrigues; Lee, Orlando; Dias, Zanoni

2015-01-01

During evolution, global mutations may alter the order and the orientation of the genes in a genome. Such mutations are referred to as rearrangement events, or simply operations. In unichromosomal genomes, the most common operations are reversals, which are responsible for reversing the order and orientation of a sequence of genes, and transpositions, which are responsible for switching the location of two contiguous portions of a genome. The problem of computing the minimum sequence of operations that transforms one genome into another - which is equivalent to the problem of sorting a permutation into the identity permutation - is a well-studied problem that finds application in comparative genomics. There are a number of works concerning this problem in the literature, but they generally do not take into account the length of the operations (i.e. the number of genes affected by the operations). Since it has been observed that short operations are prevalent in the evolution of some species, algorithms that efficiently solve this problem in the special case of short operations are of interest. In this paper, we investigate the problem of sorting a signed permutation by short operations. More precisely, we study four flavors of this problem: (i) the problem of sorting a signed permutation by reversals of length at most 2; (ii) the problem of sorting a signed permutation by reversals of length at most 3; (iii) the problem of sorting a signed permutation by reversals and transpositions of length at most 2; and (iv) the problem of sorting a signed permutation by reversals and transpositions of length at most 3. We present polynomial-time solutions for problems (i) and (iii), a 5-approximation for problem (ii), and a 3-approximation for problem (iv). Moreover, we show that the expected approximation ratio of the 5-approximation algorithm is not greater than 3 for random signed permutations with more than 12 elements. Finally, we present experimental results that show

Functional Problems and Maintenance Operations of Hydraulic Turbines

Directory of Open Access Journals (Sweden)

Liliana Topliceanu

2016-02-01

Full Text Available The exploitation in good conditions of the hydroelectric power plant imposes a rigorous maintenance of equipment and operating facilities, primarily of the turbine. The efficiency of the turbine is strongly affected by any defects which could occur during the operation. The paper makes a synthesis of the most frequent failures which have occurred during the functioning of Kaplan turbines plant and the required maintenance plan that has to be adopted. The maintenance rules for the optimal working of these turbines are also emphasized.

The problem of the first return attached to a pseudodifferential operator in dimension 3

Directory of Open Access Journals (Sweden)

Oscar F. Casas-Sánchez

2015-12-01

Full Text Available In this article we study the problem of first return associated to an elliptic pseudodifferential operator with non-radial symbol of dimension 3 over the p-adics. Resumen.El problema del primer retorno asociado a un operador seudodiferencial en dimensión 3 En este artículo estudiamos el problema del primer retorno asociado a un operador seudodiferencial elíptico con símbolo no radial de dimensión 3 sobre el cuerpo de los números pádicos.

Operational aspects, results and problems associated with R/B testing at Gentilly 2

International Nuclear Information System (INIS)

Garceau, N.; Beaudoin, R.

1991-01-01

There are many methods, some more complex or difficult to deal with than others, to verify the containment building integrity. At G-2, we chose the temperature compensation method. Our selection criteria were: 1) the greater precision of this method; 2) the possibility of executing the test with the plant running at full power; 3) short period required for the test; 4) after the technique is understood, its simplicity of execution; 5) can be easily inserted in the normal operating test program with a minimum of personnel; 6) this technique can be used at both low and high pressure. In this presentation we will succinctly discuss the different phases of the technique such as: the background, the prerequisite, the problems, the results and, finally, we will give some recommendations to facilitate the use of this method

The effect of problem-based and lecture-based instructional strategies on learner problem solving performance, problem solving processes, and attitudes

Science.gov (United States)

Visser, Yusra Laila

This study compared the effect of lecture-based instruction to that of problem-based instruction on learner performance (on near-transfer and far-transfer problems), problem solving processes (reasoning strategy usage and reasoning efficiency), and attitudes (overall motivation and learner confidence) in a Genetics course. The study also analyzed the effect of self-regulatory skills and prior-academic achievement on performance for both instructional strategies. Sixty 11th grade students at a public math and science academy were assigned to either a lecture-based instructional strategy or a problem-based instructional strategy. Both treatment groups received 18 weeks of Genetics instruction through the assigned instructional strategy. In terms of problem solving performance, results revealed that the lecture-based group performed significantly better on near-transfer post-test problems. The problem-based group performed significantly better on far-transfer post-test problems. In addition, results indicated the learners in the lecture-based instructional treatment were significantly more likely to employ data-driven reasoning in the solving of problems, whereas learners in the problem-based instructional treatment were significantly more likely to employ hypothesis-driven reasoning in problem solving. No significant differences in reasoning efficiency were uncovered between treatment groups. Preliminary analysis of the motivation data suggested that there were no significant differences in motivation between treatment groups. However, a post-research exploratory analysis suggests that overall motivation was significantly higher in the lecture-based instructional treatment than in the problem-based instructional treatment. Learner confidence was significantly higher in the lecture-based group than in the problem-based group. A significant positive correlation was detected between self-regulatory skills scores and problem solving performance scores in the problem

Classical solutions of two dimensional Stokes problems on non smooth domains. 1: The Radon integral operators

International Nuclear Information System (INIS)

Lubuma, M.S.

1991-05-01

The applicability of the Neumann indirect method of potentials to the Dirichlet and Neumann problems for the two-dimensional Stokes operator on a non smooth boundary Γ is subject to two kinds of sufficient and/or necessary conditions on Γ. The first one, occurring in electrostatic, is equivalent to the boundedness on C(Γ) of the velocity double layer potential W as well as to the existence of jump relations of potentials. The second condition, which forces Γ to be a simple rectifiable curve and which, compared to the Laplacian, is a stronger restriction on the corners of Γ, states that the Fredholm radius of W is greater than 2. Under these conditions, the Radon boundary integral equations defined by the above mentioned jump relations are solvable by the Fredholm theory; the double (for Dirichlet) and the single (for Neumann) layer potentials corresponding to their solutions are classical solutions of the Stokes problems. (author). 48 refs

Problems on triangular norms and related operators

Czech Academy of Sciences Publication Activity Database

Klement, E.P.; Mesiar, Radko; Pap, E.

2004-01-01

Roč. 23, č. 145 (2004), s. 471-479 ISSN 0165-0114 R&D Projects: GA ČR GA402/04/1026 Institutional research plan: CEZ:AV0Z1075907 Keywords : triangular norm * triangular conorm * aggregation operator Subject RIV: BA - General Mathematics Impact factor: 0.734, year: 2004

The interactive effect of paternal problem drinking and maternal problem drinking on adolescent internalizing problems.

Science.gov (United States)

Ohannessian, Christine McCauley

2015-11-01

This study examined the effects of both paternal problem drinking and maternal problem drinking on adolescent internalizing problems (depression and anxiety symptomatology). Surveys were administered to 566 10th and 11th grade students from the Mid-Atlantic region of the U.S. in the spring of 2007 and again in the spring of 2008. Although significant main effects were not observed, significant interactions were found between paternal problem drinking and maternal problem drinking for internalizing problems, especially for boys. In general, these interactions indicated that when paternal problem drinking was high, depression symptomatology and anxiety symptomatology were lower if maternal problem drinking was low. Findings from this study highlight the need to consider both paternal and maternal problem drinking when examining the effects that parental problem drinking may have on adolescent adjustment. Copyright © 2015 Elsevier Ltd. All rights reserved.

A NNIA Scheme for Timetabling Problems

Directory of Open Access Journals (Sweden)

Yu Lei

2017-01-01

Full Text Available This paper presents a memetic multiobjective optimization algorithm based on NNIA for examination timetabling problems. In this paper, the examination timetabling problem is considered as a two-objective optimization problem while it is modeled as a single-objective optimization problem generally. Within the NNIA framework, the special crossover operator is utilized to search in the solution space; two local search techniques are employed to optimize these two objectives and a diversity-keeping strategy which consists of an elitism group operator and an extension optimization operator to ensure a sufficient number of solutions in the pareto front. The proposed algorithm was tested on the most widely used uncapacitated Carter benchmarks. Experimental results prove that the proposed algorithm is a competitive algorithm.

Military Operational Research: the Sensor Coverage Problem

NARCIS (Netherlands)

Barros, A.I.; Koopmans, J.

1999-01-01

Military Operations Research is a field that has been growing since the Second World War, and in particular in the last decades. Within this vast area, Air Defence, the protection of the air space against an airborne threat, has become a hot topic. ln order to successfully protect a given zone

Math word problems for dummies

CERN Document Server

Sterling, Mary Jane

2008-01-01

Covers percentages, probability, proportions, and moreGet a grip on all types of word problems by applying them to real lifeAre you mystified by math word problems? This easy-to-understand guide shows you how to conquer these tricky questions with a step-by-step plan for finding the right solution each and every time, no matter the kind or level of problem. From learning math lingo and performing operations to calculating formulas and writing equations, you''ll get all the skills you need to succeed!Discover how to: * Translate word problems into plain English* Brush up on basic math skills* Plug in the right operation or formula* Tackle algebraic and geometric problems* Check your answers to see if they work

Agricultural problems

International Nuclear Information System (INIS)

Bickerton, George E.

1997-01-01

Although there were not reasons to deplore against major activity release from any of the 110 industrial reactors authorized to operate in US, the nuclear incident that occurred at the Three Mile Island Plant in 1979 urged the public conscience toward the necessity of readiness to cope with events of this type. The personnel of the Emergency Planning Office functioning in the frame of US Department of Agriculture has already participated in around 600 intervention drillings on a federal, local or state scale to plan, test or asses radiological emergency plans or to intervene locally. These exercises allowed acquiring a significant experience in elaborating emergency plans, planning the drillings, working out scenarios and evaluation of the potential impact of accidents from the agricultural point of view. We have also taken part in different international drillings among which the most recent are INEX 1 and RADEX 94. We have found on these occasions that the agricultural problems are essential preoccupations in most of the cases no matter if the context is international, national, local or of state level. The paper poses problems specifically related to milk, fruits and vegetables, soils, meat and meat products. Finally the paper discusses issues like drilling planning, alarm and notification, sampling strategy, access authorizations for farmers, removing of contamination wastes. A number of social, political and economical relating problems are also mentioned

EFFECT SIGNIFICANCE ASSESSMENT OF THE THERMODYNAMICAL FACTORS ON THE SOLID OXIDE FUEL CELL OPERATION

Directory of Open Access Journals (Sweden)

V. A. Sednin

2015-01-01

Full Text Available Technologies of direct conversion of the fuel energy into electrical power are an upcoming trend in power economy. Over the last decades a number of countries have created industrial prototypes of power plants on fuel elements (cells, while fuel cells themselves became a commercial product on the world energy market. High electrical efficiency of the fuel cells allows predictting their further spread as part of hybrid installations jointly with gas and steam turbines which specifically enables achieving the electrical efficiency greater than 70 %. Nevertheless, investigations in the area of increasing efficiency and reliability of the fuel cells continue. Inter alia, research into the effects of oxidizing reaction thermodynamic parameters, fuel composition and oxidation reaction products on effectiveness of the solid oxide fuel cells (SOFC is of specific scientific interest. The article presents a concise analysis of the fuel type effects on the SOFC efficiency. Based on the open publications experimental data and the data of numerical model studies, the authors adduce results of the statistical analysis of the SOFC thermodynamic parameters effect on the effectiveness of its functioning as well as of the reciprocative factors of these parameters and gas composition at the inlet and at the outlet of the cell. The presented diagrams reflect dimension of the indicated parameters on the SOFC operation effectiveness. The significance levels of the above listed factors are ascertained. Statistical analysis of the effects of the SOFC functionning process thermodynamical, consumption and concentration parameters demonstrates quintessential influence of the reciprocative factors (temperature – flow-rate and pressure – flow-rate and the nitrogen N2 and oxygen O2 concentrations on the operation efficiency in the researched range of its functioning. These are the parameters to be considered on a first-priority basis while developing mathematical models

Operant Variability: Some Random Thoughts

Science.gov (United States)

Marr, M. Jackson

2012-01-01

Barba's (2012) paper is a serious and thoughtful analysis of a vexing problem in behavior analysis: Just what should count as an operant class and how do people know? The slippery issue of a "generalized operant" or functional response class illustrates one aspect of this problem, and "variation" or "novelty" as an operant appears to fall into…

Adding control to arbitrary unknown quantum operations

Science.gov (United States)

Zhou, Xiao-Qi; Ralph, Timothy C.; Kalasuwan, Pruet; Zhang, Mian; Peruzzo, Alberto; Lanyon, Benjamin P.; O'Brien, Jeremy L.

2011-01-01

Although quantum computers promise significant advantages, the complexity of quantum algorithms remains a major technological obstacle. We have developed and demonstrated an architecture-independent technique that simplifies adding control qubits to arbitrary quantum operations—a requirement in many quantum algorithms, simulations and metrology. The technique, which is independent of how the operation is done, does not require knowledge of what the operation is, and largely separates the problems of how to implement a quantum operation in the laboratory and how to add a control. Here, we demonstrate an entanglement-based version in a photonic system, realizing a range of different two-qubit gates with high fidelity. PMID:21811242

Significance of campaigned spent fuel shipments

International Nuclear Information System (INIS)

Doman, J.W.; Tehan, T.E.

1993-01-01

Operational experience associated with spent fuel or irradiated hardware shipments to or from the General Electric Morris Facility is presented. The following specific areas are addressed: Problems and difficulties associated with meeting security and safeguard requirements of 10 CFR Part 73; problems associated with routing via railroad; problems associated with scheduling and impact on affected parties when a shipment is delayed or cancelled; and impact on training when shipments spread over many years. The lessons learned from these experiences indicate that spent fuel shipments are best conducted in dedicated open-quotes campaignsclose quotes that concentrate as much consecutive shipping activity as possible into one continuous time frame

COAL-FIRED UTILITY BOILERS: SOLVING ASH DEPOSITION PROBLEMS; TOPICAL

International Nuclear Information System (INIS)

Christopher J. Zygarlicke; Donald P. McCollor; Steven A. Benson; Jay R. Gunderson

2001-01-01

The accumulation of slagging and fouling ash deposits in utility boilers has been a source of aggravation for coal-fired boiler operators for over a century. Many new developments in analytical, modeling, and combustion testing methods in the past 20 years have made it possible to identify root causes of ash deposition. A concise and comprehensive guidelines document has been assembled for solving ash deposition as related to coal-fired utility boilers. While this report accurately captures the current state of knowledge in ash deposition, note that substantial research and development is under way to more completely understand and mitigate slagging and fouling. Thus, while comprehensive, this document carries the title ''interim,'' with the idea that future work will provide additional insight. Primary target audiences include utility operators and engineers who face plant inefficiencies and significant operational and maintenance costs that are associated with ash deposition problems. Pulverized and cyclone-fired coal boilers are addressed specifically, although many of the diagnostics and solutions apply to other boiler types. Logic diagrams, ash deposit types, and boiler symptoms of ash deposition are used to aid the user in identifying an ash deposition problem, diagnosing and verifying root causes, determining remedial measures to alleviate or eliminate the problem, and then monitoring the situation to verify that the problem has been solved. In addition to a step-by-step method for identifying and remediating ash deposition problems, this guideline document (Appendix A) provides descriptions of analytical techniques for diagnostic testing and gives extensive fundamental and practical literature references and addresses of organizations that can provide help in alleviating ash deposition problems

Schmidt number for quantum operations

International Nuclear Information System (INIS)

Huang Siendong

2006-01-01

To understand how entangled states behave under local quantum operations is an open problem in quantum-information theory. The Jamiolkowski isomorphism provides a natural way to study this problem in terms of quantum states. We introduce the Schmidt number for quantum operations by this duality and clarify how the Schmidt number of a quantum state changes under a local quantum operation. Some characterizations of quantum operations with Schmidt number k are also provided

Operation Amplifier

NARCIS (Netherlands)

Tetsuya, Saito; Nauta, Bram

2011-01-01

PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a

Operation Amplifier

NARCIS (Netherlands)

Tetsuya, S.; Nauta, Bram

2007-01-01

PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. ; SOLUTION: The operation amplifier comprises: a

FFLP problem with symmetric trapezoidal fuzzy numbers

Directory of Open Access Journals (Sweden)

Reza Daneshrad

2015-04-01

Full Text Available The most popular approach for solving fully fuzzy linear programming (FFLP problems is to convert them into the corresponding deterministic linear programs. Khan et al. (2013 [Khan, I. U., Ahmad, T., & Maan, N. (2013. A simplified novel technique for solving fully fuzzy linear programming problems. Journal of Optimization Theory and Applications, 159(2, 536-546.] claimed that there had been no method in the literature to find the fuzzy optimal solution of a FFLP problem without converting it into crisp linear programming problem, and proposed a technique for the same. Others showed that the fuzzy arithmetic operation used by Khan et al. (2013 had some problems in subtraction and division operations, which could lead to misleading results. Recently, Ezzati et al. (2014 [Ezzati, R., Khorram, E., & Enayati, R. (2014. A particular simplex algorithm to solve fuzzy lexicographic multi-objective linear programming problems and their sensitivity analysis on the priority of the fuzzy objective functions. Journal of Intelligent and Fuzzy Systems, 26(5, 2333-2358.] defined a new operation on symmetric trapezoidal fuzzy numbers and proposed a new algorithm to find directly a lexicographic/preemptive fuzzy optimal solution of a fuzzy lexicographic multi-objective linear programming problem by using new fuzzy arithmetic operations, but their model was not fully fuzzy optimization. In this paper, a new method, by using Ezzati et al. (2014’s fuzzy arithmetic operation and a fuzzy version of simplex algorithm, is proposed for solving FFLP problem whose parameters are represented by symmetric trapezoidal fuzzy number without converting the given problem into crisp equivalent problem. By using the proposed method, the fuzzy optimal solution of FFLP problem can be easily obtained. A numerical example is provided to illustrate the proposed method.

EBR-II: twenty years of operating experience

International Nuclear Information System (INIS)

Lentz, G.L.; Buschman, H.W.; Smith, R.N.

1985-01-01

Experimental Breeder Reactor No. 2 (EBR-II) is an unmoderated, sodium-cooled reactor with a design power of 62.5 MWt. For the last 20 years EBR-II has operated safely, has demonstrated stable operating characteristics, has shown excellent performance of its sodium components, and has had an excellent plant factor. These years of operating experience provide a valuable resource to the nuclear community for the development and design of future liquid metal fast reactors. This report provides a brief description of the EBR-II plant and its early operating experience, describes some recent problems of interest to the nuclear community, and also mentions some of the significant operating achievements of EBR-II. Finally, a few words and speculations on EBR-II's future are offered. 4 figs., 1 tab

Developing Information Technology for Vocational Education in Contiguous Destitute Areas Significance, Problems, and Countermeasures: The Case of the Wuling Mountain Area

Science.gov (United States)

Wang, Jie; Xu, Fenghua

2014-01-01

Using the Wuling Mountain area as a case study, the authors discuss the significance as well as five problems of developing information technology for vocational education in contiguous destitute areas. Recommendations are provided at the end of the article. [Translated by Michelle LeSourd.

Solution of some types of differential equations: operational calculus and inverse differential operators.

Science.gov (United States)

Zhukovsky, K

2014-01-01

We present a general method of operational nature to analyze and obtain solutions for a variety of equations of mathematical physics and related mathematical problems. We construct inverse differential operators and produce operational identities, involving inverse derivatives and families of generalised orthogonal polynomials, such as Hermite and Laguerre polynomial families. We develop the methodology of inverse and exponential operators, employing them for the study of partial differential equations. Advantages of the operational technique, combined with the use of integral transforms, generating functions with exponentials and their integrals, for solving a wide class of partial derivative equations, related to heat, wave, and transport problems, are demonstrated.

The Impact of Transitive Inference Operations on Mathematics ...

African Journals Online (AJOL)

This study examined the extent to which operations of transitive inference tasks have affected the mathematics problem solving abilities of pre-primary school children. Four research hypotheses were tested at 0.05 level of significance using 400 nursery school children whose ages ranged between 4.5 and 5.5 years ...

Multidomain Operations: A Subtle but Significant Transition in Military Thought

Science.gov (United States)

2016-01-01

He pointed out that whichever side loses in an electronic war will be reduced to blindness and deafness , so its weapons will be disabled, and it...reconnaissance; communications; early warning; and navigation. The conse- quences would severely affect a joint force air component commander’s planning ...operational planning that facilitates prioritized allocation of bandwidth, efficient data exchange, flexible security requirements, and the organi

A NEW MUTATION OPERATOR IN GENETIC PROGRAMMING

Directory of Open Access Journals (Sweden)

Anuradha Purohit

2013-01-01

Full Text Available This paper proposes a new type of mutation operator, FEDS (Fitness, Elitism, Depth, and Size mutation in genetic programming. The concept behind the new mutation operator is inspired from already introduced FEDS crossover operator to handle the problem of code bloating. FEDS mutation operates by using local elitism replacement in combination with depth limit and size of the trees to reduce bloat with a subsequent improvement in the performance of trees (program structures. We have designed a multiclass classifier for some benchmark datasets to test the performance of proposed mutation. The results show that when the initial run uses FEDS crossover and the concluding run uses FEDS mutation, then not only is the final result significantly improved but there is reduction in bloat also.

Operating performance of LWR nuclear generating units

International Nuclear Information System (INIS)

Pia, S.

1984-01-01

This work aims at reviewing, on the basis of historical data, the operational problem areas which explain the degree of availability and productivity achieved up to now by nuclear power plants in commercial operation in the world. The operating performance data of nuclear power plants area analysed with respect to plant type, size and other significant reference parameters and they are evaluated also by comparison with fossil generating unit data. Major performance indices data are presented for both nuclear and fossil units type and distribution of outage causes. Unplanned full outages caused by nuclear power plant equipment and components failure are particulary emphasized. The trend for unplanned full outages due to the failure of components shows decreasing numerical values in 1981 with respect to the previous years. But this result should be weighed with the increasing plant unavailability hours needed for maintenance and repair action (chiefly preventive maintenance on critical components). This means that the number and downtime of forced outage must be drastically reduced for economic reasons (production losses and problems associated with the unavailable unit unplanned replacement) as well as for plant safe and reliable operation (sudden unavailability of key components and frequency of transients associated with plant shutdown and routine startup operation)

14 CFR Special Federal Aviation... - Operating Limitations for Unscheduled Operations at Chicago's O'Hare International Airport

Science.gov (United States)

2010-01-01

.... Operators may contact the ARO at (703) 904-4452 if they have a technical problem making a Reservation using..., law enforcement, military aircraft operations or public-use aircraft operations may be accommodated... system asks for a date or time, it is expecting an input of numbers. A problem arises when entering a...

Well-posedness of nonlocal parabolic differential problems with dependent operators.

Science.gov (United States)

Ashyralyev, Allaberen; Hanalyev, Asker

2014-01-01

The nonlocal boundary value problem for the parabolic differential equation v'(t) + A(t)v(t) = f(t) (0 ≤ t ≤ T), v(0) = v(λ) + φ, 0 exact estimates in Hölder norms for the solution of two nonlocal boundary value problems for parabolic equations with dependent coefficients are established.

Operating performance and reliability of CANDU PHWR fuel channels in Canada

International Nuclear Information System (INIS)

Strachan, B.; Brown, D.R.

1983-03-01

CANDU nuclear plants use many small-diameter high-pressure fuel channels. Good operating performance from the CANDU fuel channels has made a major contribution to the world-leading operating record of the CANDU nuclear power plants. As of 1982 December 31, there were 7,480 fuel channels installed in 18 CANDU reactors over 500 MW(e) in size. Eight of these reactors have been declared in-service and have accumulated 24,000 fuel channel-years of operation. The only significant operating problems with fuel channels have been the occurrence of leaking cracks in 70 fuel channels and a larger amount of axial creep on the early reactors than was originally provided for in the design. Both of these problems have been corrected on all CANDU reactors built since the Bruce GS 'A' station and the newer reactors should exhibit even better performance

Predictors of Help-Seeking Intentions in Operation Enduring Freedom and Operation Iraqi Freedom Veterans and Service Members.

Science.gov (United States)

Porcari, Carole; Koch, Ellen I; Rauch, Sheila A M; Hoodin, Flora; Ellison, Grant; McSweeney, Lauren

2017-05-01

Despite significant numbers of Afghanistan and Iraqi veterans and service members who report symptoms of posttraumatic stress disorder, depression, anxiety, and substance abuse, the majority do not seek help for these problems. A better understanding of the help-seeking process might aid providers and administrators in outreach and provision of services for those who need them. Past research has shown several variables that influence an individual's help-seeking behavior: demographic variables, the nature and severity of a mental health problem, and psychological variables. The three goals of the study were to determine which variables predicted help-seeking intentions from various sources for a psychological problem, identify barriers to help seeking, and identify sources of help sought in the past year. All Operation Enduring Freedom and Operation Iraqi Freedom veterans and service members registered with a Midwestern VA Healthcare System between 2001 and 2007 received a letter requesting participation in an Internet-based survey. Participants completed nine questionnaires regarding their current physical and psychological health, social support, self-efficacy, public and self-stigma, and barriers to seeking help for a psychological problem. In addition, patterns of help seeking from informal (i.e., partner/spouse, family, friends) and formal (i.e., physician, psychiatrist, or psychologist, either from Veterans Affairs [VA] or the private sector) sources of help were examined. Results from the linear regression model including all formal and informal sources of help indicated a significant model fit with attitudes toward psychotherapy, social support, and current mental health status as significant coefficients. Of note, attitudes toward psychotherapy were a significant coefficient in all help-seeking models; stigma was a significant coefficient with formal and VA sources, and social support was found to be a significant predictor with informal sources

Environmental program with operational cases to reduce risk to the marine environment significantly

International Nuclear Information System (INIS)

Cline, J.T.; Forde, R.

1991-01-01

In this paper Amoco Norway Oil Company's environmental program is detailed, followed by example operational programs and achievements aimed to minimize environmental risks to the marine environment at Valhall platform. With a corporate goal to be a leader in protecting the environment, the appropriate strategies and policies that form the basis of the environmental management system are incorporated in the quality assurance programs. Also, included in the program are necessary organizational structures, responsibilities of environmental affairs and line organization personnel, compliance procedures and a waste task force obliged to implement operations improvements. An internal environmental audit system has been initiated, in addition to corporate level audits, which, when communicated to the line organization closes the environmental management loop through experience feed back. Environmental projects underway are significantly decreasing the extent and/or risk of pollution from offshore activities. The cradle to grave responsibility is assumed with waste separated offshore and onshore followed by disposal in audited sites. A $5 MM program is underway to control produced oily solids and reduce oil in produced water aiming to less than 20 ppm. When oil-based mud is used in deeper hole sections, drill solids disposed at sea average less than 60 g oil/kg dry cuttings using appropriate shaker screens, and a washing/centrifuge system to remove fines. Certain oily liquid wastes are being injected down hole whereas previously they were burned using a mud burner. Finally, a program is underway with a goal to eliminate sea discharge of oil on cuttings through injection disposal of oily wastes, drilling with alternative muds such as a cationic water base mud, and/or proper onshore disposal of oily wastes

Problems with Interagency Integration in Contemporary Operations

Science.gov (United States)

2014-12-04

also conducted other tasks that included providing security for NGO food distribution and creating a prioritized list of requirements. The Joint...operation moved into February. In several instances, United States military airdropped food and other resources into urban areas that 46 Guha-Sapir...Up to thirty percent of crops rotted in farmer’s fields due to insufficient road networks. They also identified electricity as critical. Over

Operating systems

CERN Document Server

Tsichritzis, Dionysios C; Rheinboldt, Werner

1974-01-01

Operating Systems deals with the fundamental concepts and principles that govern the behavior of operating systems. Many issues regarding the structure of operating systems, including the problems of managing processes, processors, and memory, are examined. Various aspects of operating systems are also discussed, from input-output and files to security, protection, reliability, design methods, performance evaluation, and implementation methods.Comprised of 10 chapters, this volume begins with an overview of what constitutes an operating system, followed by a discussion on the definition and pr

Inverse problems in linear transport theory

International Nuclear Information System (INIS)

Dressler, K.

1988-01-01

Inverse problems for a class of linear kinetic equations are investigated. The aim is to identify the scattering kernel of a transport equation (corresponding to the structure of a background medium) by observing the 'albedo' part of the solution operator for the corresponding direct initial boundary value problem. This means to get information on some integral operator in an integrodifferential equation through on overdetermined boundary value problem. We first derive a constructive method for solving direct halfspace problems and prove a new factorization theorem for the solutions. Using this result we investigate stationary inverse problems with respect to well posedness (e.g. reduce them to classical ill-posed problems, such as integral equations of first kind). In the time-dependent case we show that a quite general inverse problem is well posed and solve it constructively. (orig.)

Operational approach to the environmental problems in the developing countries

Energy Technology Data Exchange (ETDEWEB)

Amsyari, F

1980-01-01

Environmental programs associated with socioeconomic development are examined. In most developing countries, environmental problems affecting human health are connected with poverty, over-population, and biological pollutants. An analysis of the environmental problems associated with socioeconomic development in Surabaya City, Indonesia, is presented. An analytical methodology and a mathematical model for an integrated environmental program are described. (1 diagram, 5 references, 5 tables)

Perceiving fingers in single-digit arithmetic problems.

Science.gov (United States)

Berteletti, Ilaria; Booth, James R

2015-01-01

In this study, we investigate in children the neural underpinnings of finger representation and finger movement involved in single-digit arithmetic problems. Evidence suggests that finger representation and finger-based strategies play an important role in learning and understanding arithmetic. Because different operations rely on different networks, we compared activation for subtraction and multiplication problems in independently localized finger somatosensory and motor areas and tested whether activation was related to skill. Brain activations from children between 8 and 13 years of age revealed that only subtraction problems significantly activated finger motor areas, suggesting reliance on finger-based strategies. In addition, larger subtraction problems yielded greater somatosensory activation than smaller problems, suggesting a greater reliance on finger representation for larger numerical values. Interestingly, better performance in subtraction problems was associated with lower activation in the finger somatosensory area. Our results support the importance of fine-grained finger representation in arithmetical skill and are the first neurological evidence for a functional role of the somatosensory finger area in proficient arithmetical problem solving, in particular for those problems requiring quantity manipulation. From an educational perspective, these results encourage investigating whether different finger-based strategies facilitate arithmetical understanding and encourage educational practices aiming at integrating finger representation and finger-based strategies as a tool for instilling stronger numerical sense.

RTD problems at Darlington

International Nuclear Information System (INIS)

McAllindon, D.; Sloan, D.; Mayer, P.

1997-01-01

Resistance Temperature Detectors (RTDs) and their measurement circuit components have been a significant maintenance item at Darlington. Analysis of the problems has shown that RTDs and electrical penetrations (EPs) have been the largest sources of faults. A failure mechanism in which the RTD electrical resistance shifts upward was identified as a major source of RTD failures, which prompted a detailed failure investigation by Ontario Hydro Technologies (OHT). The investigation concluded that the root cause failure mechanism is chlorine contamination of the platinum wire during manufacture which resulted in surface damage to the wire and flaking of the wire surface during operation. Electrical penetrations in Darlington are of a pre-built modular design with two crimps internal to the EP. Spurious resistance in poor quality crimps in the EPs lead to errors in resistance measurement. The problem led to a complex and costly job to insert new modules in existing spare EPs. (author)

A problem with problem solving: motivational traits, but not cognition, predict success on novel operant foraging tasks.

Science.gov (United States)

van Horik, Jayden O; Madden, Joah R

2016-04-01

Rates of innovative foraging behaviours and success on problem-solving tasks are often used to assay differences in cognition, both within and across species. Yet the cognitive features of some problem-solving tasks can be unclear. As such, explanations that attribute cognitive mechanisms to individual variation in problem-solving performance have revealed conflicting results. We investigated individual consistency in problem-solving performances in captive-reared pheasant chicks, Phasianus colchicus , and addressed whether success depends on cognitive processes, such as trial-and-error associative learning, or whether performances may be driven solely via noncognitive motivational mechanisms, revealed through subjects' willingness to approach, engage with and persist in their interactions with an apparatus, or via physiological traits such as body condition. While subjects' participation and success were consistent within the same problems and across similar tasks, their performances were inconsistent across different types of task. Moreover, subjects' latencies to approach each test apparatus and their attempts to access the reward were not repeatable across trials. Successful individuals did not improve their performances with experience, nor were they consistent in their techniques in repeated presentations of a task. However, individuals that were highly motivated to enter the experimental chamber were more likely to participate. Successful individuals were also faster to approach each test apparatus and more persistent in their attempts to solve the tasks than unsuccessful individuals. Our findings therefore suggest that individual differences in problem-solving success can arise from inherent motivational differences alone and hence be achieved without inferring more complex cognitive processes.

Clinical significance of measurement of changes of serum IGF-II, SCC and CYFRA21-1 levels after operation in patients with carcinoma of uterine cervix

International Nuclear Information System (INIS)

Kuang Lei

2010-01-01

Objective: To explore the clinical significance of changes of serum IGF-II, SCC and CYFRA21-1 levels after operation in patients with carcinoma uterine cervix. Methods: Serum levels of IGF-II, SCC and CYFRA21-1 were determined with RIA repeatedly in 31 patients with carcinoma of uterine cervix (before operation 1 month after operation and 6 month after operation) and once in 35 controls. Results: Before operation,serum levels of IGF-II, SCC and CYFRA21-1 in the patients were significantly higher than those in the controls (P<0.01). One month after operation all the serum levels were approaching normal. Six month later,the levels in the patients without recurrence remained normal. However, the levels in the 6 patients with recurrence returned to those before operation again. Conclusion: Changes of serum IGF-II, SCC and CYFRA21-1 levels are closely related to the tumor burden and may be of prognostic importance. (authors)

The analysis and countermeasures of intravenous infusion operation assessment results analysis in nursing students at different levels

Directory of Open Access Journals (Sweden)

Jiao-rong ZHAO

2013-11-01

Full Text Available Objective:To analyze the problems existed in nursing students at different levels in the process of intravenous infusion, to make judgmental guide towards common problems in clinical teaching, to standardize nursing students’ operations at intravenous infusion, and to avoid errors and disputes. Methods: The authors analyzed the problems in secondary, tertiary, undergraduate nursing students in three levels at a provincial hospital from 2010 to 2012 during intravenous infusion therapy; and the clinical teaching administration means were also discussed. Results: the difference of the problems existed in nursing students at different levels is not significant. P values were greater than 0.05. The top five projects that lost scores are consistent. Conclusion: The key problems that can easily cause errors and disputes are those that mostly occurred in nursing students at intravenous infusion operations. In clinical teaching, judgmental guide on common problems should be emphasized, nursing students’ operations at intravenous infusion should be standardized, the critical awareness towards clinical operations should be developed, errors and disputes should be avoided, and nursing students’ sense of professionalism should be enhanced.

Application of the HGPT methodology of reactor operation problems with a nodal mixed method

International Nuclear Information System (INIS)

Baudron, A.M.; Bruna, G.B.; Gandini, A.; Lautard, J.J.; Monti, S.; Pizzigati, G.

1998-01-01

The heuristically based generalized perturbation theory (HGPT), to first and higher order, applied to the neutron field of a reactor system, is discussed in relation to quasistatic problems. This methodology is of particular interest in reactor operation. In this application it may allow an on-line appraisal of the main physical responses of the reactor system when subject to alterations relevant to normal system exploitation, e.g. control rod movement, and/or soluble boron concentration changes to be introduced, for instance, for compensating power level variations following electrical network demands. In this paper, after describing the main features of the theory, its implementation into the diffusion, 3D mixed dual nodal code MINOS of the SAPHYR system is presented. The results from a small scale investigation performed on a simplified PWR system corroborate the validity of the methodology proposed

ENEL's experience in the management of irradiated fuel. Old and new problems encountered by nuclear station operators

International Nuclear Information System (INIS)

Ariemma, A.; Cuzzaniti, M.; Zaffiro, B.; Bertini, A.

1983-01-01

The experience acquired in recent years in the management of spent fuel discharged from ENEL's reactors has revealed a substantial change in the attitude of nuclear station operators in connection with the end of the fuel cycle downstream from the reactor (back-end). While in the past, after President Carter's outline of US policy in April 1977, the utilities had to face great difficulty in reprocessing their fuel owing to inadequate capacity, today the same problem is regarded as a matter of cost-benefit analysis from an industrial standpoint and of appropriate planning for the utilization of the recovered fissile materials. Since the present technology allows spent fuel storage (dry or underwater) to be planned for rather long periods and plutonium utilization requires a very stringent schedule, the present trend is to ensure medium-term storage of spent fuel and to seek a greater flexibility in the final reprocessing stages so as to render plutonium availability consistent with the programmes for its utilization. As a consequence, the solution to the problems posed by high-activity waste disposal is being delayed, thus allowing an exhaustive and detailed analysis of all the possible solutions to be made. The paper describes a number of solutions to the problems ENEL has encountered in the fuel cycle back-end. (author)

Defining and determining the significance of impacts: concepts and methods

International Nuclear Information System (INIS)

Christensen, S.W.; Van Winkle, W.; Mattice, J.S.

1975-01-01

The term impact is conceptually and mathematically defined to be the difference in the state or value of an ecosystem with versus without the source of impact. Some resulting problems associated with the measurement of impacts based on comparisons of baseline and operational data are discussed briefly. The concept of a significant adverse impact on a biological system is operationally defined in terms of an adverse impact which, according to a proposed decision-tree, justifies rejection of a project or a change in its site, design, or mode of operation. A gradient of increasing difficulty in the prediction of impacts exists as the scope of the assessment is expanded to consider long-term, far-field impacts with respect to higher levels of biological organization (e.g., communities or ecosystems). The analytical methods available for predicting short-term, near-field impacts are discussed. Finally, the role of simulation modeling as an aid to professional judgment in predicting the long-term, far-field consequences of impacts is considered, and illustrated with an example. (U.S.)

A Parallel Computational Model for Multichannel Phase Unwrapping Problem

Science.gov (United States)

Imperatore, Pasquale; Pepe, Antonio; Lanari, Riccardo

2015-05-01

In this paper, a parallel model for the solution of the computationally intensive multichannel phase unwrapping (MCh-PhU) problem is proposed. Firstly, the Extended Minimum Cost Flow (EMCF) algorithm for solving MCh-PhU problem is revised within the rigorous mathematical framework of the discrete calculus ; thus permitting to capture its topological structure in terms of meaningful discrete differential operators. Secondly, emphasis is placed on those methodological and practical aspects, which lead to a parallel reformulation of the EMCF algorithm. Thus, a novel dual-level parallel computational model, in which the parallelism is hierarchically implemented at two different (i.e., process and thread) levels, is presented. The validity of our approach has been demonstrated through a series of experiments that have revealed a significant speedup. Therefore, the attained high-performance prototype is suitable for the solution of large-scale phase unwrapping problems in reasonable time frames, with a significant impact on the systematic exploitation of the existing, and rapidly growing, large archives of SAR data.

Islamic Education Research Problem

Directory of Open Access Journals (Sweden)

Abdul Muthalib

2012-04-01

Full Text Available This paper will discuss Islamic educational studies that is reviewing how to find, limit and define problems and problem-solving concepts. The central question of this paper is to describe how to solve the problem in Islamic educational research. A researcher or educator who has the knowledge, expertise, or special interest on education for example is usually having a sensitivity to issues relating to educational research. In the research dimension of religious education, there are three types of problems, namely: Problems foundation, structural problems and operational issues. In doing research in Islamic education someone should understand research problem, limiting and formulating the problem, how to solve the problem, other problem relating to the point of research, and research approach.

Sparsity regularization for parameter identification problems

International Nuclear Information System (INIS)

Jin, Bangti; Maass, Peter

2012-01-01

The investigation of regularization schemes with sparsity promoting penalty terms has been one of the dominant topics in the field of inverse problems over the last years, and Tikhonov functionals with ℓ p -penalty terms for 1 ⩽ p ⩽ 2 have been studied extensively. The first investigations focused on regularization properties of the minimizers of such functionals with linear operators and on iteration schemes for approximating the minimizers. These results were quickly transferred to nonlinear operator equations, including nonsmooth operators and more general function space settings. The latest results on regularization properties additionally assume a sparse representation of the true solution as well as generalized source conditions, which yield some surprising and optimal convergence rates. The regularization theory with ℓ p sparsity constraints is relatively complete in this setting; see the first part of this review. In contrast, the development of efficient numerical schemes for approximating minimizers of Tikhonov functionals with sparsity constraints for nonlinear operators is still ongoing. The basic iterated soft shrinkage approach has been extended in several directions and semi-smooth Newton methods are becoming applicable in this field. In particular, the extension to more general non-convex, non-differentiable functionals by variational principles leads to a variety of generalized iteration schemes. We focus on such iteration schemes in the second part of this review. A major part of this survey is devoted to applying sparsity constrained regularization techniques to parameter identification problems for partial differential equations, which we regard as the prototypical setting for nonlinear inverse problems. Parameter identification problems exhibit different levels of complexity and we aim at characterizing a hierarchy of such problems. The operator defining these inverse problems is the parameter-to-state mapping. We first summarize some

Intelligent decision-making models for production and retail operations

CERN Document Server

Guo, Zhaoxia

2016-01-01

This book provides an overview of intelligent decision-making techniques and discusses their application in production and retail operations. Manufacturing and retail enterprises have stringent standards for using advanced and reliable techniques to improve decision-making processes, since these processes have significant effects on the performance of relevant operations and the entire supply chain. In recent years, researchers have been increasingly focusing attention on using intelligent techniques to solve various decision-making problems. The opening chapters provide an introduction to several commonly used intelligent techniques, such as genetic algorithm, harmony search, neural network and extreme learning machine. The book then explores the use of these techniques for handling various production and retail decision-making problems, such as production planning and scheduling, assembly line balancing, and sales forecasting.

Diagnostic and Prognostic Significance of Lipid Profiles in Holstein Dairy Cattle with Displaced Abomasum: Before and After Surgical Operation

Directory of Open Access Journals (Sweden)

Arafat Khalphallah

2016-01-01

Full Text Available The study aimed to describe the pattern of changes in clinical findings and lipid metabolism profiles in dairy cattle with displacement of the abomasum (DA from day 0 until day 30 after operation. The study was conducted on DA cattle (n= 25 belonged to dairy farms in Hokkaido area, Japan. Cows were examined and sampled at days 0 (operation, 7 and 30. They were clinically and biochemically examined to estimate BCS and many serum biochemical constituents such as lecithin:cholesterol acyltransferase (LCAT and apolipoprotein B-100 (apoB-100, β-hydroxybutyric acid (BHBA, non-esterified fatty acids (NEFAs and aspartate amino transferase (AST. Based on blood BHBA at day 0, DA cows were classified into three categories; DA only (<1.2 mmol/l, DA with subclinical ketosis (DA SCK (1.2-2.4 mmol/l and DA with clinical ketosis (DA CK (≥2.5 mmol/l. The changes in the pattern of serum biochemical constituents throughout this study indicated recovery of diseased cows and significant effect of surgical operation. Serum biochemical constituents returned to their physiological values indicating that these cows were restoring their normal physiological status. This was reflected through a significant (P＜0.05 elevation of LCAT, apoB-100, and cholesterol and a significant (P＜0.05 reduction in AST, NEFAs and BHBA (Not in DA group, in all DA groups particularly at day 30 when their values compared with those at day 0. The current study also recorded no remarkable changes (P＞0.05 between the diseased groups except for NEFA and BHBA (at day 0 between DA group and the other two groups at any of the three sampling days.

Enhancement of pressurizer safety valve operability by seating design improvement

International Nuclear Information System (INIS)

Moisidis, N.T.; Ratiu, M.D.

1994-01-01

Operating conditions specific to Pressurizer Safety Valves (PSVs) have led to numerous problems and have caused industry and NRC concerns regarding the adequacy of spring loaded self-actuated safety valves for Reactor Coolant System (RCS) overpressure protection. Specific concerns are: setpoint drift, spurious actuations and leakage. Based on testing and valve construction analysis of a Crosby model 6M6 PSV, it was established that the primary contributor to the valve problems is a susceptibility to weak seating. To eliminate spring instability, a new spring washer was designed, which guides the spring and precludes its rotation from the reference installed position. Results of tests performed on a prototype PSV equipped with the modified upper spring washer has shown significant improvements in valve operability and a consistent setpoint reproducibility to less than ±1% of the PSV setpoint (testing of baseline, unmodified valve, resulted in a setpoint drift of ±2%). Enhanced valve operability will result in a significant decrease in operating and maintenance costs associated with valve maintenance and testing. In addition, the enhanced setpoint reproducibility will allow the development of a nitrogen to steam correlation for future in-house PSV testing which will result in further reductions in costs associated with valve testing

The problem of "significant risk": exploring the public health impact of criminalizing HIV non-disclosure.

Science.gov (United States)

Mykhalovskiy, Eric

2011-09-01

Using criminal law powers to respond to people living with HIV (PHAs) who expose sexual partners to HIV or transmit the virus to them is a prominent global HIV public policy issue. While there are widespread concerns about the public health impact of HIV-related criminalization, the social science literature on the topic is limited. This article responds to that gap in knowledge by reporting on the results of qualitative research conducted with service providers and PHAs in Canada. The article draws on a studies in the social organization of knowledge perspective and insights from critical criminology and work on the "medico-legal borderland." It investigates the role played by the legal concept of "significant risk" in coordinating criminal law governance and its interface with public health and HIV prevention. In doing so, the article emphasizes that exploring the public health impact of criminalization must move past the criminal law--PHA dyad to address broader social and institutional processes relevant to HIV prevention. Drawing on individual and focus group interviews, this article explores how criminal law governance shapes the activities of providers engaged in HIV prevention counseling, conceptualized as a complex of activities linking clinicians, public health officials, front-line counselors, PHAs, and others. It emphasizes three key findings: (1) the concept of significant risk poses serious problems to risk communication in HIV counseling and contributes to contradictory advice about disclosure obligations; (2) criminalization discourages PHAs' openness about HIV non-disclosure in counseling relationships; and (3) the recontextualization of public health interpretations of significant risk in criminal proceedings can intensify criminalization. Copyright © 2011 Elsevier Ltd. All rights reserved.

The radiological significance of transuranium radioisotopes released to the environment during operation of the LMFBR fuel cycle

International Nuclear Information System (INIS)

Barr, N.F.

1976-01-01

Estimates based on current knowledge and conservative assumptions indicate that release of transuranium elements from the Liquid Metal Fast Breeder Reactor (LMFBR) fuel cycle are likely to proaduce population dose commitments small compared to those produced by naturally occurring alpha emitters and globally dispersed transuranium radioisotopes from tests of nuclear weapons in the atmosphere. Potential health consequences of these releases to current and future generations are estimated to be very small compared to risks associated with the production of energy by fossil fuels. The estimates are subject to a number of uncertainties imposed by lack of knowledge. Some of the uncertainties are not likely to be greatly reduced until LMFBR facilities are designed and operated. Others may be significantly reduced prior to facility design and operation. The paper discusses the sensitivity of the estimates to uncertainties and approches to reducing those uncertainties that strongly influence the estimates. (author)

A tabu-search heuristic for solving the multi-depot vehicle scheduling problem

Directory of Open Access Journals (Sweden)

Gilmar D'Agostini Oliveira Casalinho

2014-08-01

Full Text Available Currently the logistical problems are relying quite significantly on Operational Research in order to achieve greater efficiency in their operations. Among the problems related to the vehicles scheduling in a logistics system, the Multiple Depot Vehicle Scheduling Problem (MDVSP has been addressed in several studies. The MDVSP presupposes the existence of depots that affect the planning of sequences to which travel must be performed. Often, exact methods cannot solve large instances encountered in practice and in order to take them into account, several heuristic approaches are being developed. The aim of this study was thus to solve the MDVSP using a meta-heuristic based on tabu-search method. The main motivation for this work came from the indication that only recently the use of meta-heuristics is being applied to MDVSP context (Pepin et al. 2008 and, also, the limitations listed by Rohde (2008 in his study, which used the branch-and-bound in one of the steps of the heuristic presented to solve the problem, which has increased the time resolution. The research method for solving this problem was based on adaptations of traditional techniques of Operational Research, and provided resolutions presenting very competitive results for the MDVSP such as the cost of the objective function, number of vehicles used and computational time.

Study of operating procedures in nuclear power plants: Practices and problems

International Nuclear Information System (INIS)

Morgenstern, M.H.; Barnes, V.E.; McGuire, M.V.; Radford, L.R.; Wheeler, W.A.

1987-02-01

This report describes the project activities, findings, and recommendations of a project entitled ''Program Plan for Assessing and Upgrading Operating Procedures for Nuclear Power Plants.'' The project was performed by the Pacific Northwest Laboratory and Battelle Human Affairs Research Centers for the Division of Human Factors Technology, Office of Nuclear Reactor Regulation, US Nuclear Regulatory Commission (NRC). The project team analyzed and evaluated samples of normal and abnormal operating procedures from 31 commercial nuclear power plant sites operating in the United States. The project team also visited nine nuclear power plants in the United States to obtain information on the development, use, and control of operating procedures. A peer review group was convened to advise the project team on the conduct of the project and to review and comment on the project report. The report contains findings on the usability of operating procedures and on practices concerning the development, use, an control of operating procedures in nuclear power plants. The report includes recommendations to the NRC on the need to upgrade the quality of operating procedures. The report also discusses an approach to a program plan to assess and upgrade operating procedures

Problems Facing Rural Schools.

Science.gov (United States)

Stewart, C. E.; And Others

Problems facing rural Scottish schools range from short term consideration of daily operation to long term consideration of organizational alternatives. Addressed specifically, such problems include consideration of: (1) liaison between a secondary school and its feeder primary schools; (2) preservice teacher training for work in small, isolated…

POLITICAL RISK ON THE FINANCIAL MARKET The problem of adequate scientific assessment of business operations - the naivety of economists

Directory of Open Access Journals (Sweden)

Leszek Dziawgo

2014-04-01

Full Text Available One of the significant problems of a modern economy and economics is political risk. A destructive influence of politics on the financial market cannot be ignored. It is necessary to indicate some selected specific problems of the financial market connected with politics in the area of: public finance (including EU, monetary policy and capital market. Nowadays, the scale and dynamics of political interference in the economy and finance leads to the problem of rationality in business activities. Moreover, many hidden political factors change the political risk into immeasurable political uncertainty.

From capture to simulation: connecting forward and inverse problems in fluids

KAUST Repository

Gregson, James; Ihrke, Ivo; Thuerey, Nils; Heidrich, Wolfgang

2014-01-01

We explore the connection between fluid capture, simulation and proximal methods, a class of algorithms commonly used for inverse problems in image processing and computer vision. Our key finding is that the proximal operator constraining fluid velocities to be divergence-free is directly equivalent to the pressure-projection methods commonly used in incompressible flow solvers. This observation lets us treat the inverse problem of fluid tracking as a constrained flow problem all while working in an efficient, modular framework. In addition it lets us tightly couple fluid simulation into flow tracking, providing a global prior that significantly increases tracking accuracy and temporal coherence as compared to previous techniques. We demonstrate how we can use these improved results for a variety of applications, such as re-simulation, detail enhancement, and domain modification. We furthermore give an outlook of the applications beyond fluid tracking that our proximal operator framework could enable by exploring the connection of deblurring and fluid guiding.

From capture to simulation: connecting forward and inverse problems in fluids

KAUST Repository

Gregson, James

2014-07-27

We explore the connection between fluid capture, simulation and proximal methods, a class of algorithms commonly used for inverse problems in image processing and computer vision. Our key finding is that the proximal operator constraining fluid velocities to be divergence-free is directly equivalent to the pressure-projection methods commonly used in incompressible flow solvers. This observation lets us treat the inverse problem of fluid tracking as a constrained flow problem all while working in an efficient, modular framework. In addition it lets us tightly couple fluid simulation into flow tracking, providing a global prior that significantly increases tracking accuracy and temporal coherence as compared to previous techniques. We demonstrate how we can use these improved results for a variety of applications, such as re-simulation, detail enhancement, and domain modification. We furthermore give an outlook of the applications beyond fluid tracking that our proximal operator framework could enable by exploring the connection of deblurring and fluid guiding.

Operational Research : Congress of APDIO, the Portuguese Operational Research Society

CERN Document Server

Almeida, João; Oliveira, José; Pinto, Alberto

2018-01-01

This proceedings book presents selected contributions from the XVIII Congress of APDIO (the Portuguese Association of Operational Research) held in Valença on June 28–30, 2017. Prepared by leading Portuguese and international researchers in the field of operations research, it covers a wide range of complex real-world applications of operations research methods using recent theoretical techniques, in order to narrow the gap between academic research and practical applications. Of particular interest are the applications of, nonlinear and mixed-integer programming, data envelopment analysis, clustering techniques, hybrid heuristics, supply chain management, and lot sizing and job scheduling problems. In most chapters, the problems, methods and methodologies described are complemented by supporting figures, tables and algorithms.   The XVIII Congress of APDIO marked the 18th installment of the regular biannual meetings of APDIO – the Portuguese Association of Operational Research. The meetings bring toget...

Green open location-routing problem considering economic and environmental costs

Directory of Open Access Journals (Sweden)

Eliana M. Toro

2016-12-01

Full Text Available This paper introduces a new bi-objective vehicle routing problem that integrates the Open Location Routing Problem (OLRP, recently presented in the literature, coupled with the growing need for fuel consumption minimization, named Green OLRP (G-OLRP. Open routing problems (ORP are known to be NP-hard problems, in which vehicles start from the set of existing depots and are not required to return to the starting depot after completing their service. The OLRP is a strategic-level problem involving the selection of one or many depots from a set of candidate locations and the planning of delivery radial routes from the selected depots to a set of customers. The concept of radial paths allows us to use a set of constraints focused on maintaining the radiality condition of the paths, which significantly simplifies the set of constraints associated with the connectivity and capacity requirements and provides a suitable alternative when compared with the elimination problem of sub-tours traditionally addressed in the literature. The emphasis in the paper will be placed on modeling rather than solution methods. The model proposed is formulated as a bi-objective problem, considering the minimization of operational costs and the minimization of environmental effects, and it is solved by using the epsilon constraint technique. The results illustrate that the proposed model is able to generate a set of trade-off solutions leading to interesting conclusions about the relationship between operational costs and environmental impact.

An investigation into the application of modern heuristic optimisation techniques to problems in power and processing utilities

International Nuclear Information System (INIS)

Dahal, Keshav Prasad

2000-01-01

The work contained in this thesis demonstrates that there is a significant requirement for the development and application of new optimisation techniques for solving industrial scheduling problems, in order to achieve a better schedule with significant economic and operational impact. An investigation of how modern heuristic approaches, such as genetic algorithm (GA), simulated annealing (SA), fuzzy logic and hybrids of these techniques, may be developed, designed and implemented appropriately for solving short term and long term NP-hard scheduling problems that exist in electric power utilities and process facilities. GA and SA based methods are developed for generator maintenance scheduling using a novel integer encoding and appropriate GA and SA operators. Three hybrid approaches (an inoculated GA, a GA/SA and a GA with fuzzy logic) are proposed in order to improve the solution performance, and to take advantage of any flexibilities inherent in the problem. Five different GA-based approaches are investigated for solving the generation scheduling problem. Of those, a knowledge-based hybrid GA approach achieves better solutions in a shorter computational time. This approach integrates problem specific knowledge, heuristic dispatch calculation and linear programming within the GA-framework. The application of a GA-based methodology is proposed for the scheduling of storage tanks of a water treatment facility. The proposed approach is an integration of a GA and a heuristic rule-base. The GA string considers the tank allocation problem, and the heuristic approach solves the rate determination problems within the framework of the GA. For optimising the schedule of operations of a bulk handling port facility, a generic modelling tool is developed characterising the operational and maintenance activities of the facility. A GA-based approach is integrated with the simulation software for optimising the scheduling of operations of the facility. Each of these approaches is

A Problem-Solving Approach to Teaching Operant Conditioning

Science.gov (United States)

Shields, Carolyn; Gredler, Margaret

2003-01-01

Psychology students frequently have misconceptions of basic concepts in operant conditioning. Prior classroom observations revealed that most students defined positive reinforcement as reward and equated negative reinforcement and punishment. Students also labeled positive reinforcement as rewarding good behavior and negative reinforcement as…

Operational Reconnaissance: Identifying the Right Problems in a Complex World

Science.gov (United States)

2015-05-23

velocity of human interactions and the diverse demographics among populations as having critical impacts on land operations. Understanding these can have a...Achtung Panzer! Translated by Christopher Duffy. London, England: Arms and Armour Press, 1995. Echevarria II, Antonio J. “American Operational Art

Startup and operation at the Browns Ferry Nuclear Plant (includes March 22, 1975, cabel tray fire)

International Nuclear Information System (INIS)

Metke, R.G.

1977-01-01

This paper addresses itself to significant events experienced during startup and operation of the three unit Browns Ferry Nuclear Plant located near Athens, Alabama. It consists of two major parts: (1) Resolution of significant equipment problems, and (2) Description of the March 22, 1975, cable tray fire. Identification of principal problems and their solutions should help prevent similar obstacles and related costly delays at other nuclear stations

Evaluation of PWR's operating experience. Significant events which influenced French nuclear power program

International Nuclear Information System (INIS)

Dupuis, M.C.

1986-10-01

This report discusses developments or changes in safety policy (whether statutory or otherwise) and in plant design and operation, which, in many cases, correlate. When considering these events, it is important to bear in mind the standardization policy characterizing the French nuclear power program, and implying central decision-making, both for the safety authorities and the operating utility [fr

The human body and weightlessness operational effects, problems and countermeasures

CERN Document Server

Thornton, William

2017-01-01

This book focuses on all of the major problems associated with the absence of body weight in space, by analyzing effects, adaption, and re-adaptation upon returning to Earth, using sound scientific principles embedded in a historical context. Serious problems for space travelers range from Space Motion Sickness (SMS) to recently discovered ocular effects that may permanently impair vision. Fluid loss and shifts, spinal changes, and bone and muscle loss are also all results of weightlessness. Starting with a brief definition and history of weightlessness, the authors then address in detail each problem as well as the countermeasures aimed at alleviating them. In some cases, alternative hypotheses regarding what can and should be attempted are also presented. As plans for long-term missions to the Moon and Mars develop, it will be essential to find countermeasures to weightlessness that are effective for missions that could span years.

Modified and fuzzified general problem solver for 'monkey and banana' problem, 2

International Nuclear Information System (INIS)

Sano, Norihide; Takahashi, Ryoichi.

1991-01-01

The automatic operation is important for the in-service inspection of the operating nuclear power station or the decommission of retired plants. The master and slave control will be introduced for work-robot control. It is desirable that the slave involves the capability of problem solving. This paper assumed that the slave involved the general problem solver algorithm. In view of having solved the puzzle of the 'monkey and banana', the slave system is regarded as the reasonable alternative which incorporates the capability of problem solving. Basically, the GPS solves a problem by reducing the difference between an initial state and a goal state, and hence the performance of GPS depends on selecting the difference to be reduced. The usual GPS is given in advance the ordering which indicates the importance of the differences. In this paper, the GPS was improved by making use of the rules which decide the order. When several choices are found on the given difference, the fuzzified decision to determine the action is demonstrated in this paper. (author)

Analysis of human performance problems at the Swedish nuclear power plants

International Nuclear Information System (INIS)

Bento, J.P.

1988-01-01

The last five years of operation of all Swedish nuclear power plants have been studied with respect to human performance problems by analysing all scrams and licensee event reports (LERs). Thus, the study covers 165 scrams and 1318 LERs. As general results, 39% of the scrams and 27% of the LERs, as an average for the years 1983-1987, are caused by human performance problems. Among the items studied, emphasis has been put on the analysis of the causal categories involved in human performance problems resulting in plant events. The most significant causal categories appear to be Work organization, Procedures not followed, Work place ergonomics and Human variability

A joint routing and speed optimization problem

OpenAIRE

Fukasawa, Ricardo; He, Qie; Santos, Fernando; Song, Yongjia

2016-01-01

Fuel cost contributes to a significant portion of operating cost in cargo transportation. Though classic routing models usually treat fuel cost as input data, fuel consumption heavily depends on the travel speed, which has led to the study of optimizing speeds over a given fixed route. In this paper, we propose a joint routing and speed optimization problem to minimize the total cost, which includes the fuel consumption cost. The only assumption made on the dependence between the fuel cost an...

Critical corrosion issues and mitigation strategies impacting the operability of LWR's

International Nuclear Information System (INIS)

Jones, R.L.

1996-01-01

Recent corrosion experience in US light water reactor nuclear power plants is reviewed with emphasis on mitigation strategies to control the cost of corrosion to LWR operators. Many components have suffered corrosion problems resulting in industry costs of billions of dollars. The most costly issues have been stress corrosion cracking of stainless steel coolant piping in boiling water reactors and corrosion damage to steam generator tubes in pressurized water reactors. Through industry wide R and D programs these problems are now understood and mitigation strategies have been developed to address the issues in a cost effective manner. Other significant corrosion problems for both reactor types are briefly reviewed. Tremendous progress has been made in controlling corrosion, however, minimizing its impact on plant operations will present a continuing challenge throughout the remaining service lives of these power plants

Perceiving fingers in single-digit arithmetic problems

Directory of Open Access Journals (Sweden)

Ilaria eBerteletti

2015-03-01

Full Text Available In this study, we investigate in children the neural underpinnings of finger representation and finger movement involved in single-digit arithmetic problems. Evidence suggests that finger representation and finger-based strategies play an important role in learning and understanding arithmetic. Because different operations rely on different networks, we compared activation for subtraction and multiplication problems in independently localized finger somatosensory and motor areas and tested whether activation was related to skill. Brain activations from children between 8 and 13 years of age revealed that only subtraction problems significantly activated finger motor areas, suggesting reliance on finger-based strategies. In addition, larger subtraction problems yielded greater somatosensory activation than smaller problems, suggesting a greater reliance on finger representation for larger numerical values. Interestingly, better performance in subtraction problems was associated with lower activation in the finger somatosensory area. Our results support the importance of fine-grained finger representation in arithmetical skill and are the first neurological evidence for a functional role of the somatosensory finger area in proficient arithmetical problem solving, in particular for those problems requiring quantity manipulation. From an educational perspective, these results encourage investigating whether different finger-based strategies facilitate arithmetical understanding and encourage educational practices aiming at integrating finger representation and finger-based strategies as a tool for instilling stronger numerical sense.

Noticing relevant problem features: activating prior knowledge affects problem solving by guiding encoding

Science.gov (United States)

Crooks, Noelle M.; Alibali, Martha W.

2013-01-01

This study investigated whether activating elements of prior knowledge can influence how problem solvers encode and solve simple mathematical equivalence problems (e.g., 3 + 4 + 5 = 3 + __). Past work has shown that such problems are difficult for elementary school students (McNeil and Alibali, 2000). One possible reason is that children's experiences in math classes may encourage them to think about equations in ways that are ultimately detrimental. Specifically, children learn a set of patterns that are potentially problematic (McNeil and Alibali, 2005a): the perceptual pattern that all equations follow an “operations = answer” format, the conceptual pattern that the equal sign means “calculate the total”, and the procedural pattern that the correct way to solve an equation is to perform all of the given operations on all of the given numbers. Upon viewing an equivalence problem, knowledge of these patterns may be reactivated, leading to incorrect problem solving. We hypothesized that these patterns may negatively affect problem solving by influencing what people encode about a problem. To test this hypothesis in children would require strengthening their misconceptions, and this could be detrimental to their mathematical development. Therefore, we tested this hypothesis in undergraduate participants. Participants completed either control tasks or tasks that activated their knowledge of the three patterns, and were then asked to reconstruct and solve a set of equivalence problems. Participants in the knowledge activation condition encoded the problems less well than control participants. They also made more errors in solving the problems, and their errors resembled the errors children make when solving equivalence problems. Moreover, encoding performance mediated the effect of knowledge activation on equivalence problem solving. Thus, one way in which experience may affect equivalence problem solving is by influencing what students encode about the

Logic problems and solutions for memory signal of SEC pump in FQNP

International Nuclear Information System (INIS)

Lu Yanfei; Dang Xiaoqiang; Zhou Li; Ye Aiai

2014-01-01

In the Fuqing nuclear power plant, as a nuclear safety function system, the essential service water system is set two trains, and there are two pumps in each train. These pumps can be switched automatically according to the operation conditions. The signal which performs the automatic switch function called memory signal. This paper introduces the definition and role of the memory signal firstly, and then analyzes the logic of the two mutual backup SEC pumps, and the implementation method based on DCS platform. Finally, this paper presents the problems of memory signal during the commissioning and operation. Meanwhile, this paper proposes solutions to solve these problems, and analyzes the risk of the solutions, as well the significance for later units. (authors)

On psichological problem of NPP operation and control

International Nuclear Information System (INIS)

Mashin, V.A.

1994-01-01

The role of psichological factor as a reserve for increasing NPP safety connected with human factor is discussed. It is emphasized that the process of NPP personnel professional training should not be restricted by formation of a certain set of knowledge, skills and experience. It is necessary to initiate ability for constant self-developing. Control for assurance of effective interaction of the whole NPP personnel is an important problem

Synergy, a co-operative innovation for joint operations

International Nuclear Information System (INIS)

Todd, C.; Feuchtwanger, T.; Moberg, R.; Lesser, L.

1993-01-01

Industry cooperation in the operation of the large Swan Hills oil field in western Alberta is described. Declining production and increasing costs required innovative approaches to field operation. Traditional operation involved one operator making the majority of decisions with funding controlled by numerous non-operating joint owners, and can suffer from interaction problems due to the inherenty competitive nature of the petroleum industry. The new mode of operation stresses trust, cooperation, teamwork, resource sharing, and continuous improvement. The synergy involves sharing best practices, information, knowledge and expertise, combining resources, and standardizing procedures and specifications. The new mode of operation has resulted in an improved performance of up to 15%. The cooperation lessons learnt at Swan Hills may have broad application across the petroleum industry. 6 refs., 6 figs

THE PROBLEM OF SUPPLIER

OpenAIRE

Raffo Lecca, Eduardo

2014-01-01

This is a famous problem from the annals of literature in operations research. G. Dantzig in [1] refers to W.W. Jacobs with his paper "The Caterer Problem" Nav. Log Res. Quart. 1 1954; as well as Gaddum, Hoffman and Sokolowsky "On the Solution of the Caterer Problem" Naval Res Logist. Quart., Vol.1, No. 3, september, 1954, and William Prager "On the Caterer Problem" of Management Sci, Vol 3, No. 1 october 1956 and Management Sci, Vol 3, No. 2 january 1957. Subsequently both G. Hadley presents...

Reliability studies of high operating temperature MCT photoconductor detectors

Science.gov (United States)

Wang, Wei; Xu, Jintong; Zhang, Yan; Li, Xiangyang

2010-10-01

This paper concerns HgCdTe (MCT) infrared photoconductor detectors with high operating temperature. The near room temperature operation of detectors have advantages of light weight, less cost and convenient usage. Their performances are modest and they suffer from reliable problems. These detectors face with stability of the package, chip bonding area and passivation layers. It's important to evaluate and improve the reliability of such detectors. Defective detectors were studied with SEM(Scanning electron microscope) and microscopy. Statistically significant differences were observed between the influence of operating temperature and the influence of humidity. It was also found that humility has statistically significant influence upon the stability of the chip bonding and passivation layers, and the amount of humility isn't strongly correlated to the damage on the surface. Considering about the commonly found failures modes in detectors, special test structures were designed to improve the reliability of detectors. An accelerated life test was also implemented to estimate the lifetime of the high operating temperature MCT photoconductor detectors.

Audits reveal ten common environmental problems

International Nuclear Information System (INIS)

Buys, M.W.

1992-01-01

The old saying that open-quotes an ounce of prevention is worth a pound of cureclose quotes rings particularly true in environmental matters in the 1990s. Environmental problems can potentially lead to expensive fines, costly cleanups, negative public relations, and even criminal sanctions against members of the corporation. A recurring pattern of problems has been noted during the performance of environmental disposition, acquisition, and compliance assessments of many different operators in most of the producing states. The ten most common problems found in oilfield audits are discussed here in an effort to enhance the awareness of operators

Impacts of Reinsurance Operations on Significant Items of the Financial Statements of Commercial Insurance Companies According to Czech Accounting Legislation and International Accounting Standards

OpenAIRE

Jana Gláserová; Eva Vávrová

2015-01-01

The principal aim of the paper is to determine the impact of reinsurance operations in commercial insurance companies, in accordance with the relevant accounting legislation, for certain significant items of the financial statements. In actual fact, the reinsurance operations affect the profit of a commercial insurance company, following the financial statements. The prerequisite for fulfilling the objective of the paper is to analyse the accounting legislation for reinsurance operations in c...

An Adaptive Evolutionary Algorithm for Traveling Salesman Problem with Precedence Constraints

Directory of Open Access Journals (Sweden)

Jinmo Sung

2014-01-01

Full Text Available Traveling sales man problem with precedence constraints is one of the most notorious problems in terms of the efficiency of its solution approach, even though it has very wide range of industrial applications. We propose a new evolutionary algorithm to efficiently obtain good solutions by improving the search process. Our genetic operators guarantee the feasibility of solutions over the generations of population, which significantly improves the computational efficiency even when it is combined with our flexible adaptive searching strategy. The efficiency of the algorithm is investigated by computational experiments.

Coordination Scheme for Restructuring Business Operation of the Single Period Newsvendor Problem

Directory of Open Access Journals (Sweden)

Chiuh-Cheng Chyu

2013-01-01

Full Text Available This paper presents a coordination scheme for a single period newsvendor problem when both supplier and retailer of the supply chain agree to change the business operation from a market decision power sharing system (Model 1 to a unique decision maker system (Model 2. The supplier is assumed to be a risk-averse decision maker and he will undertake the product quality risk in both models. Model 1 is game theoretic, where the supplier controls the wholesale price, but the retailer controls the order quantity and market price. The bargaining process ends when the supplier has found a wholesale price that maximizes the value of his sales revenue minus the product quality cost. Model 2 is a centralized system where the supplier possesses all decision powers of the market. In general, Model 2 will generate higher total revenue than Model 1. The aim of this research is to propose a satisfying compromise based on consignment policy to resolve the revenue-sharing conflict in Model 2 due to the additional revenue. An example is provided to illustrate the two models and the proposed coordination scheme, along with managerial insights on the models’ benefits. The impacts of several parameters on the scheme are also presented and discussed.

Calm Multi-Baryon Operators

Directory of Open Access Journals (Sweden)

Berkowitz Evan

2018-01-01

Full Text Available There are many outstanding problems in nuclear physics which require input and guidance from lattice QCD calculations of few baryons systems. However, these calculations suffer from an exponentially bad signal-to-noise problem which has prevented a controlled extrapolation to the physical point. The variational method has been applied very successfully to two-meson systems, allowing for the extraction of the two-meson states very early in Euclidean time through the use of improved single hadron operators. The sheer numerical cost of using the same techniques in two-baryon systems has so far been prohibitive. We present an alternate strategy which offers some of the same advantages as the variational method while being significantly less numerically expensive. We first use the Matrix Prony method to form an optimal linear combination of single baryon interpolating fields generated from the same source and different sink interpolating fields. Very early in Euclidean time this optimal linear combination is numerically free of excited state contamination, so we coin it a calm baryon. This calm baryon operator is then used in the construction of the two-baryon correlation functions.To test this method, we perform calculations on the WM/JLab iso-clover gauge configurations at the SU(3 flavor symmetric point with mπ~ 800 MeV — the same configurations we have previously used for the calculation of two-nucleon correlation functions. We observe the calm baryon significantly removes the excited state contamination from the two-nucleon correlation function to as early a time as the single-nucleon is improved, provided non-local (displaced nucleon sources are used. For the local two-nucleon correlation function (where both nucleons are created from the same space-time location there is still improvement, but there is significant excited state contamination in the region the single calm baryon displays no excited state contamination.

Enhancement of pressurizer safety valve operability by seating design improvement

International Nuclear Information System (INIS)

Moisidis, N.T.; Ratiu, M.D.

1995-01-01

Operating conditions specific to pressurizer safety valves (PSVs) have led to numerous problems and have caused industry and NRC concerns regarding the adequacy of spring-loaded self-actuated safety valves for reactor coolant system (RCS) overpressure protection. Specific concerns are: setpoint drift, spurious actuations, and pressure protection. Specific concerns are: setpoint drift, spurious actuations, and leakage. Based on testing and valve construction analysis of a Crosby model 6M6 PSV (Moisidis and Ratiu, 1992), it was established that the primary contributor to the valve problems is a susceptibility to weak seating. To eliminate spring instability, a new spring washer was designed, which guides the spring and precludes its rotation from the reference installed position. Results of tests performed on a prototype PSV equipped with the modified upper spring washer has shown significant improvements in valve operability and a consistent setpoint reproducibility to less than ±1% of the PSV setpoint (testing of baseline, unmodified valve, resulted in a setpoint drift of ± 2%). Enhanced valve operability will result in a significant decrease in operating and maintenance costs associated with valve maintenance and testing. In addition, the enhanced setpoint reproducibility will allow the development of a nitrogen to steam correlation for future in-house PSV testing which will result in further reductions in costs associated with valve testing

Greenhouse gases emission assessment in residential sector through buildings simulations and operation optimization

International Nuclear Information System (INIS)

Stojiljković, Mirko M.; Ignjatović, Marko G.; Vučković, Goran D.

2015-01-01

Buildings use a significant amount of primary energy and largely contribute to greenhouse gases emission. Cost optimality and cost effectiveness, including cost-optimal operation, are important for the adoption of energy efficient and environmentally friendly technologies. The long-term assessment of buildings-related greenhouse gases emission might take into account cost-optimal operation of their energy systems. This is often not the case in the literature. Long-term operation optimization problems are often of large scale and computationally intensive and time consuming. This paper formulates a bottom-up methodology relying on an efficient, but precise operation optimization approach, applicable to long-term problems and use with buildings simulations. We suggest moving-horizon short-term optimization to determine near-optimal operation modes and show that this approach, applied to flexible energy systems without seasonal storage, have satisfactory efficiency and accuracy compared with solving problem for an entire year. We also confirm it as a valuable pre-solve technique. Approach applicability and the importance of energy systems optimization are illustrated with a case study considering buildings envelope improvements and cogeneration and heat storage implementation in an urban residential settlement. EnergyPlus is used for buildings simulations while mixed integer linear programming optimization problems are constructed and solved using the custom-built software and the branch-and-cut solver Gurobi Optimizer. - Highlights: • Bottom-up approach for greenhouse gases emission assessment is presented. • Short-term moving-horizon optimization is used to define operation regimes. • Operation optimization and buildings simulations are connected with modeling tool. • Illustrated optimization method performed efficiently and gave accurate results.

The Daily Operational Brief: Fostering Daily Readiness, Care Coordination, and Problem-Solving Accountability in a Large Pediatric Health Care System.

Science.gov (United States)

Donnelly, Lane F; Basta, Kathryne C; Dykes, Anne M; Zhang, Wei; Shook, Joan E

2018-01-01

At a pediatric health system, the Daily Operational Brief (DOB) was updated in 2015 after three years of operation. Quality and safety metrics, the patient volume and staffing assessment, and the readiness assessment are all presented. In addition, in the problem-solving accountability system, problematic issues are categorized as Quick Hits or Complex Issues. Walk-the-Wall, a biweekly meeting attended by hospital senior administrative leadership and quality and safety leaders, is conducted to chart current progress on Complex Issues. The DOB provides a daily standardized approach to evaluate readiness to provide care to current patients and improvement in the care to be provided for future patients. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.

Reactor operation

CERN Document Server

Shaw, J

2013-01-01

Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

Sturm-Liouville operators and applications

CERN Document Server

Marchenko, Vladimir A

2011-01-01

The spectral theory of Sturm-Liouville operators is a classical domain of analysis, comprising a wide variety of problems. Besides the basic results on the structure of the spectrum and the eigenfunction expansion of regular and singular Sturm-Liouville problems, it is in this domain that one-dimensional quantum scattering theory, inverse spectral problems, and the surprising connections of the theory with nonlinear evolution equations first become related. The main goal of this book is to show what can be achieved with the aid of transformation operators in spectral theory as well as in their

Teamwork and error in the operating room: analysis of skills and roles.

Science.gov (United States)

Catchpole, K; Mishra, A; Handa, A; McCulloch, P

2008-04-01

To analyze the effects of surgical, anesthetic, and nursing teamwork skills on technical outcomes. The value of team skills in reducing adverse events in the operating room is presently receiving considerable attention. Current work has not yet identified in detail how the teamwork and communication skills of surgeons, anesthetists, and nurses affect the course of an operation. Twenty-six laparoscopic cholecystectomies and 22 carotid endarterectomies were studied using direct observation methods. For each operation, teams' skills were scored for the whole team, and for nursing, surgical, and anesthetic subteams on 4 dimensions (leadership and management [LM]; teamwork and cooperation; problem solving and decision making; and situation awareness). Operating time, errors in surgical technique, and other procedural problems and errors were measured as outcome parameters for each operation. The relationships between teamwork scores and these outcome parameters within each operation were examined using analysis of variance and linear regression. Surgical (F(2,42) = 3.32, P = 0.046) and anesthetic (F(2,42) = 3.26, P = 0.048) LM had significant but opposite relationships with operating time in each operation: operating time increased significantly with higher anesthetic but decreased with higher surgical LM scores. Errors in surgical technique had a strong association with surgical situation awareness (F(2,42) = 7.93, P skills of the nurses (F(5,1) = 3.96, P = 0.027). Detailed analysis of team interactions and dimensions is feasible and valuable, yielding important insights into relationships between nontechnical skills, technical performance, and operative duration. These results support the concept that interventions designed to improve teamwork and communication may have beneficial effects on technical performance and patient outcome.

Solving radwaste problems

International Nuclear Information System (INIS)

Oyen, L.C.

1976-01-01

The combination of regulatory changes and increased waste volume has resulted in design changes in waste processing systems. Problems resulting from waste segregation as a basis for design philosophy are considered, and solutions to the problems are suggested. The importance of operator training, maintenance procedures, good housekeeping, water management, and offsite shipment of solids is discussed. Flowsheets for radioactive waste processing systems for boiling water reactors and pressurized water reactors are included

OPERATIONAL DISTRIBUTION OF THE TRAIN TRAFFIC VOLUME ON THE SECTIONS OF RAILWAY OPERATING DOMAIN

Directory of Open Access Journals (Sweden)

G. Ya. Моzolevich

2013-10-01

Full Text Available Purpose. The task of the operational distribution of train traffic volume on the sections of operating domain is the optimization one. It is solved in the operational conditions by the dispatch station. The article sets the problem of formalizing and finding the new ways to solve this urgent problem. Methodology. A new approach to solving the problem of operational distribution of train traffic volume on the sections of the rail network with a choice of routes for all train traffics was proposed. Findings. A study of possible routes for the train traffic handle on the operating domain used for mass freight transportations between Krivyi Rih and Donbas was carried out. The use of the proposed method allowed us to obtain a rational distribution of trains on the rail network sections. Originality. The method of train traffic volume distribution in the network under operational conditions was improved. The method, as opposed to the current one allows one to select the route of separate units handle (according to the criteria of the weighted average cost for 1 ton of cargo. Practical value. The use of the proposed technology of the operational distribution of train traffic volume will increase the efficiency of the railways in general and ensure the competitiveness of rail transportations. The methodology implementation involves the use of railway dispatch station for the automated workplaces with appropriate informational support.

Global gradient estimates for divergence-type elliptic problems involving general nonlinear operators

Science.gov (United States)

Cho, Yumi

2018-05-01

We study nonlinear elliptic problems with nonstandard growth and ellipticity related to an N-function. We establish global Calderón-Zygmund estimates of the weak solutions in the framework of Orlicz spaces over bounded non-smooth domains. Moreover, we prove a global regularity result for asymptotically regular problems which are getting close to the regular problems considered, when the gradient variable goes to infinity.

Dual ant colony operational modal analysis parameter estimation method

Science.gov (United States)

Sitarz, Piotr; Powałka, Bartosz

2018-01-01

Operational Modal Analysis (OMA) is a common technique used to examine the dynamic properties of a system. Contrary to experimental modal analysis, the input signal is generated in object ambient environment. Operational modal analysis mainly aims at determining the number of pole pairs and at estimating modal parameters. Many methods are used for parameter identification. Some methods operate in time while others in frequency domain. The former use correlation functions, the latter - spectral density functions. However, while some methods require the user to select poles from a stabilisation diagram, others try to automate the selection process. Dual ant colony operational modal analysis parameter estimation method (DAC-OMA) presents a new approach to the problem, avoiding issues involved in the stabilisation diagram. The presented algorithm is fully automated. It uses deterministic methods to define the interval of estimated parameters, thus reducing the problem to optimisation task which is conducted with dedicated software based on ant colony optimisation algorithm. The combination of deterministic methods restricting parameter intervals and artificial intelligence yields very good results, also for closely spaced modes and significantly varied mode shapes within one measurement point.

New heuristics for planning operating rooms.

NARCIS (Netherlands)

Molina-Pariente, J.M.; Hans, Elias W.; Framinan, J.M.; Gomez-Cia, T.

2015-01-01

We tackle the operating room planning problem of the Plastic Surgery and Major Burns Specialty of the University Hospital “Virgen del Rocio” in Seville (Spain). The decision problem is to assign an intervention date and an operating room to a set of surgeries on the waiting list, minimizing access

A case study of hospital operations management.

Science.gov (United States)

Cheng, T C

1987-12-01

This paper discusses a study to investigate various operations management problems in a newly opened, modern regional hospital in Hong Kong. The findings of the study reveal that there exist in the hospital a number of current and potential problem areas. Recommendations for solving these problems are suggested with a view to improving the overall operational efficiency and effectiveness of the hospital.

The etiology of behavioral problems and competencies in very young twins.

Science.gov (United States)

Saudino, Kimberly J; Carter, Alice S; Purper-Ouakil, Diane; Gorwood, Philip

2008-02-01

Although genetic and environmental influences on behavior problems in middle childhood and adolescence have been well-studied, little is known about the etiology of behavior problems in very early childhood. The present study explores genetic and environmental contributions to individual differences in behavior problems and competences in an infant-toddler sample of twins. There were 1,950 twin pairs (mean age=23.8 months) who were rated by parents on the Infant-Toddler Social and Emotional Assessment. All four domains (Externalizing, Internalizing, Dysregulation, Competence) and 20 subscales-indices on the Infant-Toddler Social and Emotional Assessment displayed significant heritability. There were also substantial shared environmental influences operating on most of the domains and subscales. Compared with behavior problems, behavioral competencies were less heritable and more influenced by shared environments. (c) 2008 APA, all rights reserved

Agent Orange Exposure and Monoclonal Gammopathy of Undetermined Significance: An Operation Ranch Hand Veteran Cohort Study.

Science.gov (United States)

Landgren, Ola; Shim, Youn K; Michalek, Joel; Costello, Rene; Burton, Debra; Ketchum, Norma; Calvo, Katherine R; Caporaso, Neil; Raveche, Elizabeth; Middleton, Dan; Marti, Gerald; Vogt, Robert F

2015-11-01

Multiple myeloma has been classified as exhibiting "limited or suggestive evidence" of an association with exposure to herbicides in Vietnam War veterans. Occupational studies have shown that other pesticides (ie, insecticides, herbicides, fungicides) are associated with excess risk of multiple myeloma and its precursor state, monoclonal gammopathy of undetermined significance (MGUS); however, to our knowledge, no studies have uncovered such an association in Vietnam War veterans. To examine the relationship between MGUS and exposure to Agent Orange, including its contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in Vietnam War veterans. This was a prospective cohort study conducted in 2013 to 2014, testing for MGUS in serum specimens collected and stored in 2002 by the Air Force Health Study (AFHS). The relevant exposure data collected by the AFHS was also used. We tested all specimens in 2013 without knowledge of the exposure status. The AFHS included former US Air Force personnel who participated in Operation Ranch Hand (Ranch Hand veterans) and other US Air Force personnel who had similar duties in Southeast Asia during the same time period (1962 to 1971) but were not involved in herbicide spray missions (comparison veterans). Agent Orange was used by the US Air Force personnel who conducted aerial spray missions of herbicides (Operation Ranch Hand) in Vietnam from 1962 to 1971. We included 479 Ranch Hand veterans and 479 comparison veterans who participated in the 2002 follow-up examination of AFHS. Agent Orange and TCDD. Serum TCDD levels were measured in 1987, 1992, 1997, and 2002. Risk of MGUS measured by prevalence, odds ratios (ORs), and 95% CIs. The 479 Ranch Hand veterans and 479 comparison veterans had similar demographic and lifestyle characteristics and medical histories. The crude prevalence of overall MGUS was 7.1% (34 of 479) in Ranch Hand veterans and 3.1% (15 of 479) in comparison veterans. This translated into a 2.4-fold increased risk

Measures for simultaneous minimization of alkali related operating problems, Phase 2; Aatgaerder foer samtidig minimering av alkalirelaterade driftproblem, Etapp 2. Ramprogram

Energy Technology Data Exchange (ETDEWEB)

Gyllenhammar, Marianne; Herstad Svaerd, Solvie; Davidsson, Kent; Aamand, Lars-Erik; Steenari, Britt-Marie; Folkeson, Nicklas; Pettersson, Jesper; Svensson, Jan-Erik; Boss, Anna; Johansson, Linda; Kassman, Haakan

2007-12-15

Combustion of an increasing amount of biofuel and waste woods has resulted in certain environmental advantages, including decreased emissions of fossil CO{sub 2}, SO{sub 2} and metals. On the other hand, a number of chloride and alkali related operational problems have occurred which are related to combustion of these fuels. Alkali related operational problems have been studied in a project consisting of two parts. The overall scope has been to characterise the operational problems and to study measures to minimise them. The first part was reported in Vaermeforsk report 997. In part two, additional measures have been included in the test plan and initial corrosion has been studied linked to the different measures. The tests have also in part two been carried out at the 12 MW CFB boiler at Chalmers. The effect of the selected measures has been investigated concerning both deposit formation and bed agglomeration, and at the same time emissions and other operational conditions were characterised. The second part of the project has among other things focused on: To investigate measures which decrease the content of alkali and chloride in the deposits, and consequently decrease the risk for corrosion (by investigating the initial corrosion). Focus was also on trying to explain favourable effects. To investigate if it is possible to combine a rather low dosage of kaolin and injection of ammonium sulphate. This was done in order to reduce both bed agglomeration and problems from deposits during combustion of fuels rich in chlorine. To investigate if co-combustion with sewage sludge, de-inking sludge or peat with high ash content, could give similar advantages as conventional additives. Investigate if ash from PFBC (coal ash and dolomite) is possible to use as an alternative bed material. In the reference case, straw pellets were co-combusted together with wood pellets. This fuel mixture gave high alkali and chlorine contents. Alkali was in surplus of chlorine. The

Operator ordering and supersymmetry (an old problem becomes new)

International Nuclear Information System (INIS)

De Alfaro, V.; Fubini, S.; Roncadelli, M.; Furlan, G.

1987-11-01

Supersymmetric quantum mechanics in curved space is investigated. The role of supersymmetry and of invariance under general coordinate transformation in solving the operator ordering ambiguity is discussed. 8 refs

Real significance of skin contamination is

International Nuclear Information System (INIS)

Sudmann, R.H.

1983-01-01

For five decades, health physicists have discussed the thickness, area, significance of radioactive contamination and the exposures to various portions of the skin. Concern about instances of skin contamination extend beyond the resultant organ dose simply because it is a recognizable and quantifiable event. As such, there is a tendency for management and regulatory agencies to use it as a trend indicator. The final result is a score card similar to the list of OSHA reportable accidents. In fact, the skin contamination incidence rate has a somewhat different meaning to the health physicist, to the manager, and to the regulator. The question must then be asked, What is the true significance of skin contamination, Is it the resultant skin dose, Is it an indicator of loss of control, Is it both or neither. In order to answer these questions, Rockwell Hanford Operations began analysis of the previous five years records of skin contamination cases. Since by policy each incidence of skin contamination is documented, a large percentage of the 425 records analyzed were of low level activity (less than 100 dpm/cm 2 ) on the extremeties, primarily hands and fingers. Most of these cases were readily decontaminated with soap and water. Individual elements studied included: detection/monitoring methods and limits; impact of type of operation on the incidence rate; causes of and methods for reduction of the incidence rate; reporting and documentation; and dose assessment. Results of the study indicate that skin contamination rarely presents a beta dose problem because it is normally highly localized on the extremeties. Only in unusual cases does it represent a potential for internal deposition. Thus, the real importance of skin contamination incidence is as an indicator of deteriorating conditions and should be reviewed by health physicists, managers and regulators as such

Energy problems of developing countries and the development co-operation

Energy Technology Data Exchange (ETDEWEB)

Mutanen, K; Sahrman, K

1984-12-15

The technology, economy and problems of energy sector in developing countries are presented as well as the possibilities of solving energy problems, with special emphasis on how to adapt Finnish energy know-how to the conditions existing in the developing countries. The population in the developing countries has grown explosively. The worst energy problem due to this growth is the shortage of firewood. The fact that wood is used for burning is one reason for the formation of deserts. Today already about one hundred million people in developing countries suffer from shortage of energy. In the following 20-30 years it will threaten already about one billion people. Poverty in the developing countries prevents the use of fossil fuels like oil. It is likely that the developing countries already in the coming decades will have to start to use new and renewable sources of energy, like these are solar and wind energy as well as hydroelectric power. The efficiency of burning fire wood should rapidly be improved. On the other hand reforestration should be increased. Also fossil fuels are needed before new sources of energy can be used. All over the world there has been interest in the energy problems of the developing countries. The World Bank and other financing bodies are increasing their financial aid for different kinds of energy projects. The Finnish development aid is primarily bilateral and concentrated in certain countries. In the 1980's the energy sector will be one of the main fields in our development aid, at the same time as the portion of our development aid from gross national income is increasing.

Optimizing integrated airport surface and terminal airspace operations under uncertainty

Science.gov (United States)

Bosson, Christabelle S.

In airports and surrounding terminal airspaces, the integration of surface, arrival and departure scheduling and routing have the potential to improve the operations efficiency. Moreover, because both the airport surface and the terminal airspace are often altered by random perturbations, the consideration of uncertainty in flight schedules is crucial to improve the design of robust flight schedules. Previous research mainly focused on independently solving arrival scheduling problems, departure scheduling problems and surface management scheduling problems and most of the developed models are deterministic. This dissertation presents an alternate method to model the integrated operations by using a machine job-shop scheduling formulation. A multistage stochastic programming approach is chosen to formulate the problem in the presence of uncertainty and candidate solutions are obtained by solving sample average approximation problems with finite sample size. The developed mixed-integer-linear-programming algorithm-based scheduler is capable of computing optimal aircraft schedules and routings that reflect the integration of air and ground operations. The assembled methodology is applied to a Los Angeles case study. To show the benefits of integrated operations over First-Come-First-Served, a preliminary proof-of-concept is conducted for a set of fourteen aircraft evolving under deterministic conditions in a model of the Los Angeles International Airport surface and surrounding terminal areas. Using historical data, a representative 30-minute traffic schedule and aircraft mix scenario is constructed. The results of the Los Angeles application show that the integration of air and ground operations and the use of a time-based separation strategy enable both significant surface and air time savings. The solution computed by the optimization provides a more efficient routing and scheduling than the First-Come-First-Served solution. Additionally, a data driven analysis is

1/f and the Earthquake Problem: Scaling constraints that facilitate operational earthquake forecasting

Science.gov (United States)

yoder, M. R.; Rundle, J. B.; Turcotte, D. L.

2012-12-01

The difficulty of forecasting earthquakes can fundamentally be attributed to the self-similar, or "1/f", nature of seismic sequences. Specifically, the rate of occurrence of earthquakes is inversely proportional to their magnitude m, or more accurately to their scalar moment M. With respect to this "1/f problem," it can be argued that catalog selection (or equivalently, determining catalog constraints) constitutes the most significant challenge to seismicity based earthquake forecasting. Here, we address and introduce a potential solution to this most daunting problem. Specifically, we introduce a framework to constrain, or partition, an earthquake catalog (a study region) in order to resolve local seismicity. In particular, we combine Gutenberg-Richter (GR), rupture length, and Omori scaling with various empirical measurements to relate the size (spatial and temporal extents) of a study area (or bins within a study area) to the local earthquake magnitude potential - the magnitude of earthquake the region is expected to experience. From this, we introduce a new type of time dependent hazard map for which the tuning parameter space is nearly fully constrained. In a similar fashion, by combining various scaling relations and also by incorporating finite extents (rupture length, area, and duration) as constraints, we develop a method to estimate the Omori (temporal) and spatial aftershock decay parameters as a function of the parent earthquake's magnitude m. From this formulation, we develop an ETAS type model that overcomes many point-source limitations of contemporary ETAS. These models demonstrate promise with respect to earthquake forecasting applications. Moreover, the methods employed suggest a general framework whereby earthquake and other complex-system, 1/f type, problems can be constrained from scaling relations and finite extents.; Record-breaking hazard map of southern California, 2012-08-06. "Warm" colors indicate local acceleration (elevated hazard

The evolution of an operant ecologist.

Science.gov (United States)

Smith, Gerard P

2002-04-01

George Collier has maintained a research program concerned with the controls of eating for forty-three years. In the first ten years, Collier approached the problem within the operant conditioning framework proposed by Skinner. This consisted of the intrameal analysis of the reflex strength of a food-rewarded operant in short sessions in food-deprived rats. At the end of the first decade, Collier shifted his attack on the problem by studying the ecological control of meal patterns by procurement and consummatory costs in free-feeding rats. This paper analyzes the reasons for this apparently abrupt evolution from operant conditioning to operant ecology and concludes that they accumulated over about ten years and were intellectual and personal, not technical or professional. This paper also summarizes the major achievements of the research program of operant ecology, notes some emerging problems with economic explanations of ecological controls, and argues that Collier's robust and quantitative behavioral results are ripe for physiological analysis. Copyright 2002 Elsevier Science Ltd.

Does preoperative breast MRI significantly impact on initial surgical procedure and re-operation rates in patients with screen-detected invasive lobular carcinoma?

International Nuclear Information System (INIS)

Sinclair, K.; Sakellariou, S.; Dawson, N.; Litherland, J.

2016-01-01

Aim: To investigate whether magnetic resonance imaging (MRI) changes the management of patients with screen-detected invasive lobular carcinoma (ILC). Materials and methods: A retrospective, controlled, single-centre analysis of 138 cases of screen-detected ILC was performed. All patients were assessed by a single multidisciplinary team as to whether preoperative MRI altered the initial management decision or reduced re-operation rates. Results: Forty-three percent of patients had preoperative MRI. MRI guided surgical management in 40.7% patients. Primary mastectomy rates were not significantly different between the MRI and non-MRI groups (32% and 30% respectively, p=0.71). The MRI group had a lower secondary surgery rate (6.8% versus 15.2%); however, the results did not reach statistical significance, and there were no unnecessary mastectomies. Conclusion: MRI can be used appropriately to guide primary surgery in screen-detected ILC cases and affects the initial management decision in 40.7% of patients. It does not significantly affect the overall mastectomy rate or re-operation rates, but reduces the likelihood of the latter. As a result of this review, the authors' local policy for the use of MRI in screen-detected ILC patients has been modified. For patients undergoing mastectomy for ILC, MRI is no longer performed routinely to search for contralateral malignancy as this has no proven added benefit. - Highlights: • Breast magnetic resonance imaging (MRI) allows more accurate tumour assessment and detects additional foci of disease in invasive lobular carcinoma (ILC). • Over the study's 3 year time frame, MRI guided surgical management of 40.7% screen-detected ILC patients scanned. • No statistically significant difference in mastectomy rates between MRI and non MRI groups. • Observed lower re-operation rate (6.8%-v-15.2%) in MRI group not statistically significant. • No MRI benefit for contralateral disease detection in ILC patients for

Generation of quantum logic operations from physical Hamiltonians

International Nuclear Information System (INIS)

Zhang Jun; Whaley, K. Birgitta

2005-01-01

We provide a systematic analysis of the physical generation of single- and two-qubit quantum operations from Hamiltonians available in various quantum systems for scalable quantum information processing. We show that generation of single-qubit operations can be transformed into a steering problem on the Bloch sphere, which represents all R z -equivalence classes of single-qubit operations, whereas the two-qubit problem can be generally transformed into a steering problem in a tetrahedron representing all the local-equivalence classes of two-qubit operations (the Weyl chamber). We use this approach to investigate several physical examples for the generation of two-qubit operations. The steering approach provides useful guidance for the realization of various quantum computation schemes

Differences in the Processes of Solving Physics Problems between Good Physics Problem Solvers and Poor Physics Problem Solvers.

Science.gov (United States)

Finegold, M.; Mass, R.

1985-01-01

Good problem solvers and poor problem solvers in advanced physics (N=8) were significantly different in their ability in translating, planning, and physical reasoning, as well as in problem solving time; no differences in reliance on algebraic solutions and checking problems were noted. Implications for physics teaching are discussed. (DH)

Claims of operators, non-operators and third parties arising from oil and gas operations

International Nuclear Information System (INIS)

Block, R.W.; Semadeni, T.

1999-01-01

There has come a resurgence in the number of companies involved in the oil and gas industry seeking protection from their creditors because of the recent weakness in commodity prices. Because most operations in this industry are conducted jointly, a single insolvency can lead to a toppling of other participants in the joint venture and beyond. The problem is to minimize one's losses if other members of the joint venture become insolvent. An examination is included of some remedies which may be available to operators, non-operators and third parties when faced with an insolvent oil and gas participant. The remedies which may be available to the non-operator that is owed moneys by its operator are discussed. The remedies that the operator has against its non-operators, with an emphasis on the nature of the operator's lien and the right of set-off, are described. A brief review is included of some of the remedies that might be available to a third party as against the operators and non-operators. Some s uggestions are included for directors, bankers, third parties, non-operators and operators

Impacts of Reinsurance Operations on Significant Items of the Financial Statements of Commercial Insurance Companies According to Czech Accounting Legislation and International Accounting Standards

Directory of Open Access Journals (Sweden)

Jana Gláserová

2015-01-01

Full Text Available The principal aim of the paper is to determine the impact of reinsurance operations in commercial insurance companies, in accordance with the relevant accounting legislation, for certain significant items of the financial statements. In actual fact, the reinsurance operations affect the profit of a commercial insurance company, following the financial statements. The prerequisite for fulfilling the objective of the paper is to analyse the accounting legislation for reinsurance operations in commercial insurance companies. Attention will be devoted also to the method of accounting for reinsurance operations and their specific reporting in various parts of the financial statements of commercial insurance companies. The partial aim of this paper is to identify significant differences in the area of accounting of commercial insurance companies, based on the comparison of accounting practices of the issues examined in accordance with IAS/IFRS. In the conclusion, the authors will address the latest development of necessary steps in adopting the concept of IFRS 4 Phase II and accomplishing the process of the application of IFRS 4 Phase II to the accounts of commercial insurance companies.

The diversity and beauty of applied operator theory

CERN Document Server

Potts, Daniel; Stollmann, Peter; Wenzel, David

2018-01-01

This book presents 29 invited articles written by participants of the International Workshop on Operator Theory and its Applications held in Chemnitz in 2017. The contributions include both expository essays and original research papers illustrating the diversity and beauty of insights gained by applying operator theory to concrete problems. The topics range from control theory, frame theory, Toeplitz and singular integral operators, Schrödinger, Dirac, and Kortweg-de Vries operators, Fourier integral operator zeta-functions, C*-algebras and Hilbert C*-modules to questions from harmonic analysis, Monte Carlo integration, Fibonacci Hamiltonians, and many more. The book offers researchers in operator theory open problems from applications that might stimulate their work and shows those from various applied fields, such as physics, engineering, or numerical mathematics how to use the potential of operator theory to tackle interesting practical problems.

The concerned significant others of people with gambling problems in a national representative sample in Sweden - a 1 year follow-up study.

Science.gov (United States)

Svensson, Jessika; Romild, Ulla; Shepherdson, Emma

2013-11-21

Research into the impact of problem gambling on close social networks is scarce with the majority of studies only including help-seeking populations. To date only one study has examined concerned significant others (CSOs) from an epidemiological perspective and it did not consider gender. The aim of this study is to examine the health, social support, and financial situations of CSOs in a Swedish representative sample and to examine gender differences. A population study was conducted in Sweden in 2008/09 (n = 15,000, response rate 63%). Respondents were defined as CSOs if they reported that someone close to them currently or previously had problems with gambling. The group of CSOs was further examined in a 1-year follow up (weighted response rate 74% from the 8,165 respondents in the original sample). Comparisons were also made between those defined as CSOs only at baseline (47.7%, n = 554) and those defined as CSOs at both time points. In total, 18.2% of the population were considered CSOs, with no difference between women and men. Male and female CSOs experienced, to a large extent, similar problems including poor mental health, risky alcohol consumption, economic hardship, and arguments with those closest to them. Female CSOs reported less social support than other women and male CSOs had more legal problems and were more afraid of losing their jobs than other men. One year on, several problems remained even if some improvements were found. Both male and female CSOs reported more negative life events in the 1 year follow-up. Although some relationships are unknown, including between the CSOs and the individuals with gambling problems and the causal relationships between being a CSO and the range of associated problems, the results of this study indicate that gambling problems not only affect the gambling individual and their immediate close family but also the wider social network. A large proportion of the population can be defined as a CSO, half of whom are

Simultaneous bilateral stereotactic procedure for deep brain stimulation implants: a significant step for reducing operation time.

Science.gov (United States)

Fonoff, Erich Talamoni; Azevedo, Angelo; Angelos, Jairo Silva Dos; Martinez, Raquel Chacon Ruiz; Navarro, Jessie; Reis, Paul Rodrigo; Sepulveda, Miguel Ernesto San Martin; Cury, Rubens Gisbert; Ghilardi, Maria Gabriela Dos Santos; Teixeira, Manoel Jacobsen; Lopez, William Omar Contreras

2016-07-01

OBJECT Currently, bilateral procedures involve 2 sequential implants in each of the hemispheres. The present report demonstrates the feasibility of simultaneous bilateral procedures during the implantation of deep brain stimulation (DBS) leads. METHODS Fifty-seven patients with movement disorders underwent bilateral DBS implantation in the same study period. The authors compared the time required for the surgical implantation of deep brain electrodes in 2 randomly assigned groups. One group of 28 patients underwent traditional sequential electrode implantation, and the other 29 patients underwent simultaneous bilateral implantation. Clinical outcomes of the patients with Parkinson's disease (PD) who had undergone DBS implantation of the subthalamic nucleus using either of the 2 techniques were compared. RESULTS Overall, a reduction of 38.51% in total operating time for the simultaneous bilateral group (136.4 ± 20.93 minutes) as compared with that for the traditional consecutive approach (220.3 ± 27.58 minutes) was observed. Regarding clinical outcomes in the PD patients who underwent subthalamic nucleus DBS implantation, comparing the preoperative off-medication condition with the off-medication/on-stimulation condition 1 year after the surgery in both procedure groups, there was a mean 47.8% ± 9.5% improvement in the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) score in the simultaneous group, while the sequential group experienced 47.5% ± 15.8% improvement (p = 0.96). Moreover, a marked reduction in the levodopa-equivalent dose from preoperatively to postoperatively was similar in these 2 groups. The simultaneous bilateral procedure presented major advantages over the traditional sequential approach, with a shorter total operating time. CONCLUSIONS A simultaneous stereotactic approach significantly reduces the operation time in bilateral DBS procedures, resulting in decreased microrecording time, contributing to the optimization of functional

Hamiltonian cycle problem and Markov chains

CERN Document Server

Borkar, Vivek S; Filar, Jerzy A; Nguyen, Giang T

2014-01-01

This book summarizes a line of research that maps certain classical problems of discrete mathematics and operations research - such as the Hamiltonian cycle and the Travelling Salesman problems - into convex domains where continuum analysis can be carried out.

Liquid radwaste processing, operational experience utilizing Duratek Mobile Process System (MPS)

International Nuclear Information System (INIS)

Hunkele, W.; Jensen, C.E.; Duratek Corp., Beltsville, MD)

1985-01-01

The use of Duratek's Mobile Process System (MPS) employing sluiceable pressure vessels and improved operational techniques generates operational efficiencies including volume reduction (VR), reduced personnel labor and exposure and higher flowrates for cleanup of liquid radwaste streams in an operating nuclear power plant (Salem Generating Station). Significant additional VR is achievable based on laboratory and on-site experience utilizing Durasil 70. Under high conductivity, actual waste stream conditions, this proprietary media has demonstrated through-puts of a magnitude 15 times higher than organic cation resin. A long-term problem, cobalt species removal, is mitigated by this media

Co-operatives and Normative Control

DEFF Research Database (Denmark)

Bregn, Kirsten; Jagd, Søren

1992-01-01

This paper explores the conditions for applying normative control in co-operatives. For normative control to be effective two conditions are found particularly important: Individuals must be morally involved and the organization must have a system of making it possible to link common norms...... and individual action. If these conditions are not fulfilled, as may be the case in many co-operatives, normative control cannot be expected to work. The problems of normative control in co-operatives may then not be caused by the use of normative control as such, but may instead be a problem of securing...

Some spectral equivalences between Schroedinger operators

International Nuclear Information System (INIS)

Dunning, C; Hibberd, K E; Links, J

2008-01-01

Spectral equivalences of the quasi-exactly solvable sectors of two classes of Schroedinger operators are established, using Gaudin-type Bethe ansatz equations. In some instances the results can be extended leading to full isospectrality. In this manner we obtain equivalences between PT-symmetric problems and Hermitian problems. We also find equivalences between some classes of Hermitian operators

Schema building profiles among elementary school students in solving problems related to operations of addition to fractions on the basis of mathematic abilities

Science.gov (United States)

Gembong, S.; Suwarsono, S. T.; Prabowo

2018-03-01

Schema in the current study refers to a set of action, process, object and other schemas already possessed to build an individual’s ways of thinking to solve a given problem. The current study aims to investigate the schemas built among elementary school students in solving problems related to operations of addition to fractions. The analyses of the schema building were done qualitatively on the basis of the analytical framework of the APOS theory (Action, Process, Object, and Schema). Findings show that the schemas built on students of high and middle ability indicate the following. In the action stage, students were able to add two fractions by way of drawing a picture or procedural way. In the Stage of process, they could add two and three fractions. In the stage of object, they could explain the steps of adding two fractions and change a fraction into addition of fractions. In the last stage, schema, they could add fractions by relating them to another schema they have possessed i.e. the least common multiple. Those of high and middle mathematic abilities showed that their schema building in solving problems related to operations odd addition to fractions worked in line with the framework of the APOS theory. Those of low mathematic ability, however, showed that their schema on each stage did not work properly.

Teamwork and problem solving in the control room

International Nuclear Information System (INIS)

Nygard, F.I.; Dedon, J.M.; Fuld, R.B.

1989-01-01

The importance of teamwork and communications in the control room of a nuclear power plant has been the subject of significant attention during the 10 yr since the Three Mile Island accident. The ability to conduct effective problem solving, especially under unexpected conditions, requires that the control room crew be well trained in techniques that produce synergism and avoid ambiguous or conflicting interactions. This paper describes the foundations of a training program developed and conducted by Combustion Engineering to produce a winning team in the control room. The complete licensed operations staffs of three utilities, Florida Power ampersand Light, Louisiana Power ampersand Light, and Omaha Public Power District, have completed this program. Thus, the results of the experience of ∼150 licensed operators is reported

Fuel handling problems at KANUPP

International Nuclear Information System (INIS)

Ahmed, I.; Mazhar Hasan, S.; Mugtadir, A.

1991-01-01

KANUPP experienced two abnormal fuel and fuel handling related problems during the year 1990. One of these had arisen due to development of end plate to end plate coupling between the two bundles at the leading end of the fuel string in channel HO2-S. The incident occurred when attempts were being made to fuel this channel. Due to pulling of sticking bundles into the acceptor fuelling machine (north) magazine, which was not designed to accommodate two bundles, a magazine rotary stop occurred. The forward motion of the charge tube was simultaneously discovered to be restricted. The incident led to stalling of fuelling machine locked on to the channel HO2, necessitating a reactor shut down. Removal of the fuelling machine was accomplished sometime later after draining of the channel. The second incident which made the fuelling of channel KO5-N temporarily inexecutable, occurred during attempts to remove its north end shield plug when this channel came up for fuelling. The incident resulted due to breaking of the lugs of the shield plug, making its withdrawal impossible. The Plant however kept operating with suspended fuelling of channel KO5, until it could no longer sustain a further increase in fuel burnup at the maximum rating position. Resolving both these problems necessitated draining of the respective channels, leaving the resident fuel uncovered for the duration of the associated operation. Due to substantial difference in the oxidation temperatures Of UO 2 and Zircaloy and its influence as such on the cooling requirement, it was necessary either to determine explicitly that the respective channels did not contain defective fuel bundles or wait for time long enough to allow the decay heat to reduce to manageable proportions. This had a significant bearing on the Plant down time necessary for the rectification of the problems. This paper describes the two incidents in detail and dwells upon the measures adopted to resolve the related problems. (author)

Fuel handling problems at KANUPP

Energy Technology Data Exchange (ETDEWEB)

Ahmed, I; Mazhar Hasan, S; Mugtadir, A [Karachi Nuclear Power Plant (KANUPP), Karachi (Pakistan)

1991-04-01

KANUPP experienced two abnormal fuel and fuel handling related problems during the year 1990. One of these had arisen due to development of end plate to end plate coupling between the two bundles at the leading end of the fuel string in channel HO2-S. The incident occurred when attempts were being made to fuel this channel. Due to pulling of sticking bundles into the acceptor fuelling machine (north) magazine, which was not designed to accommodate two bundles, a magazine rotary stop occurred. The forward motion of the charge tube was simultaneously discovered to be restricted. The incident led to stalling of fuelling machine locked on to the channel HO2, necessitating a reactor shut down. Removal of the fuelling machine was accomplished sometime later after draining of the channel. The second incident which made the fuelling of channel KO5-N temporarily inexecutable, occurred during attempts to remove its north end shield plug when this channel came up for fuelling. The incident resulted due to breaking of the lugs of the shield plug, making its withdrawal impossible. The Plant however kept operating with suspended fuelling of channel KO5, until it could no longer sustain a further increase in fuel burnup at the maximum rating position. Resolving both these problems necessitated draining of the respective channels, leaving the resident fuel uncovered for the duration of the associated operation. Due to substantial difference in the oxidation temperatures Of UO{sub 2} and Zircaloy and its influence as such on the cooling requirement, it was necessary either to determine explicitly that the respective channels did not contain defective fuel bundles or wait for time long enough to allow the decay heat to reduce to manageable proportions. This had a significant bearing on the Plant down time necessary for the rectification of the problems. This paper describes the two incidents in detail and dwells upon the measures adopted to resolve the related problems. (author)

An Analysis of the Network Selection Problem for Heterogeneous Environments with User-Operator Joint Satisfaction and Multi-RAT Transmission

Directory of Open Access Journals (Sweden)

J. J. Escudero-Garzás

2017-01-01

Full Text Available The trend in wireless networks is that several wireless radio access technologies (RATs coexist in the same area, forming heterogeneous networks in which the users may connect to any of the available RATs. The problem of associating a user to the most suitable RAT, known as network selection problem (NSP, is of capital importance for the satisfaction of the users in these emerging environments. However, also the satisfaction of the operator is important in this scenario. In this work, we propose that a connection may be served by more than one RAT by using multi-RAT terminals. We formulate the NSP with multiple RAT association based on utility functions that take into consideration both user’s satisfaction and provider’s satisfaction. As users are characterized according to their expected quality of service, our results exhaustively analyze the influence of the user’s profile, along with the network topology and the type of applications served.

Flowchart-format emergency operating procedures-strengths and weaknesses

International Nuclear Information System (INIS)

Barnes, V.E.; Bongarra, J.P. Jr.

1989-01-01

An increasing number of nuclear power plant licensees are converting their text-format emergency operating procedures (EOPs) to flowcharts. Findings of a recent study of the flowchart-format EOPs indicate that the flowchart format appears to solve several significant usability problems associated with text-format EOPs, but also introduces other types of usability concerns. This paper discusses some of the strengths and weaknesses of the flowchart format for presenting EOPs

The Concept of “Fraud”. Cooperation of Russian Telecom Operators in the Fight Agains Hackers

Directory of Open Access Journals (Sweden)

D. V. Sokolov

2010-09-01

Full Text Available Separate, legally significant, the definition of “fraud” in a telecom environment at the moment does not exist. Each country separately solves the problem through the introduction of the Criminal Code. There are attempts of a number of countries and organizations to solve this problem, but the Russian communications operators show lack of activity in this field.

76 FR 50759 - Applications and Amendments to Facility Operating Licenses Involving Proposed No Significant...

Science.gov (United States)

2011-08-16

... Company, LLC (EGC), Docket No. 50-254, Quad Cities Nuclear Power Station (QCNPS), Unit 1, Rock Island... operation SLMCPR or either of the SLMCPR values for Unit 2. This change is needed to support the next cycle of operation (i.e., Cycle 22) for QCNPS Unit 1 for cycle exposure greater than 4000 MWd/MT, which is...

LAMPF operations at 500 μA

International Nuclear Information System (INIS)

Hagerman, D.C.

1979-01-01

LAMPF now operates reliably producing 500 μA of H + beam and a few μA of H - beam or 10 nA polarized H - beam. Beam loss in the accelerator is quite acceptable at these currents. This level of performance has been achieved through solution of a wide variety of accelerator problems and a continuous evolution of the experimental areas. The future of the facility is promising both in terms of the existing experimental programs and the opportunities for significant facility improvement projects

Experience in integrating the operator contributions in the PRA of actual operating plants

International Nuclear Information System (INIS)

Potash, L.M.; Stewart, M.; Dietz, P.E.; Lewis, C.M.; Dougherty, E.M. Jr.

1982-01-01

While working on the human factors' portion of the Oconee Probabilistic Risk Assessment, we identified several major problems that inhibit any effort to handle operator error in PRAs. The approaches we developed should help to direct future efforts in dealing with these problems

Driverless operation for public passenger transport systems

Energy Technology Data Exchange (ETDEWEB)

Kehl, R. [Siemens AG, Erlangen (Germany). Bereich Verkehrstechnik

2001-07-01

The author presents the automation of new and existing lines as a possible solution to the twin problems of the growing need for public transport and the threat of collapse facing many public transport systems in the big conurbations as they wrestle against overloading. It emerges that automatic, driverless operation is a suitable approach to making systems more flexible and more attractive. Automation can increase the capacities of existing systems significantly and thus help them gain more passengers. (orig.)

The problems of Visaginas town

International Nuclear Information System (INIS)

Schiurov, V.

1998-01-01

The problems of Visaginas are specific and, first of all, connected with the operation of the Ignalina nuclear power plant and cultural development of Visaginas ethnic minorities, lack of skilled specialists employed in different spheres. Some difficulties we have with the learning of the official language. A strong well-reasoned opinion of the scientists corresponds to our practical directions: the problems of the town of Visaginas are not only the problems of its inhabitants but also a composite part of the problems of the Ignalina nuclear power plant region. (author)

Operational procedures - industry observations and opportunities for improvement

International Nuclear Information System (INIS)

Davey, E.

2003-01-01

The purpose of this paper is to relate some of the commonly encountered problems with operational procedures in the nuclear industry and offer practical suggestions for their elimination. The paper is based on recent consultant experience in assisting industry clients with human performance related design and assessment initiatives. Operational procedures are a key part of an integrated system design. Procedures provide the specified instructions for actions people are to undertake in operating a facility to achieve production and safety goals. While organizations continue to make substantial investments in procedure development and maintenance, problems with procedures continue to occur, as evidenced through operating inefficiencies, errors, and events. The paper reviews the role procedures play in facility operations, comments on current development and maintenance practices, discusses the extent of human performance related problems attributed to procedure deficiencies, reviews commonly encountered problems with design and implementation of procedures, and offers suggestions on how some of these issues might be addressed in the future. (author)

Green Virtualization for Multiple Collaborative Cellular Operators

KAUST Repository

Farooq, Muhammad Junaid

2017-06-05

This paper proposes and investigates a green virtualization framework for infrastructure sharing among multiple cellular operators whose networks are powered by a combination of conventional and renewable sources of energy. Under the proposed framework, the virtual network formed by unifying radio access infrastructures of all operators is optimized for minimum energy consumption by deactivating base stations (BSs) with low traffic loads. The users initially associated to those BSs are off-loaded to neighboring active ones. A fairness criterion for collaboration based on roaming prices is introduced to cover the additional energy costs incurred by host operators. The framework also ensures that any collaborating operator is not negatively affected by its participation in the proposed virtualization. A multi-objective linear programming problem is formulated to achieve energy and cost efficiency of the networks\\' operation by identifying the set of inter-operator roaming prices. For the case when collaboration among all operators is infeasible due to profitability, capacity, or power constraints, an iterative algorithm is proposed to determine the groups of operators that can viably collaborate. Results show significant energy savings using the proposed virtualization as compared to the standalone case. Moreover, collaborative operators exploiting locally generated renewable energy are rewarded more than traditional ones.

Solving Flexible Job-Shop Scheduling Problem Using Gravitational Search Algorithm and Colored Petri Net

Directory of Open Access Journals (Sweden)

Behnam Barzegar

2012-01-01

Full Text Available Scheduled production system leads to avoiding stock accumulations, losses reduction, decreasing or even eliminating idol machines, and effort to better benefitting from machines for on time responding customer orders and supplying requested materials in suitable time. In flexible job-shop scheduling production systems, we could reduce time and costs by transferring and delivering operations on existing machines, that is, among NP-hard problems. The scheduling objective minimizes the maximal completion time of all the operations, which is denoted by Makespan. Different methods and algorithms have been presented for solving this problem. Having a reasonable scheduled production system has significant influence on improving effectiveness and attaining to organization goals. In this paper, new algorithm were proposed for flexible job-shop scheduling problem systems (FJSSP-GSPN that is based on gravitational search algorithm (GSA. In the proposed method, the flexible job-shop scheduling problem systems was modeled by color Petri net and CPN tool and then a scheduled job was programmed by GSA algorithm. The experimental results showed that the proposed method has reasonable performance in comparison with other algorithms.

On the significance of the noise model for the performance of a linear MPC in closed-loop operation

DEFF Research Database (Denmark)

Hagdrup, Morten; Boiroux, Dimitri; Mahmoudi, Zeinab

2016-01-01

This paper discusses the significance of the noise model for the performance of a Model Predictive Controller when operating in closed-loop. The process model is parametrized as a continuous-time (CT) model and the relevant sampled-data filtering and control algorithms are developed. Using CT...... models typically means less parameters to identify. Systematic tuning of such controllers is discussed. Simulation studies are conducted for linear time-invariant systems showing that choosing a noise model of low order is beneficial for closed-loop performance. (C) 2016, IFAC (International Federation...

Separable quadratic stochastic operators

International Nuclear Information System (INIS)

Rozikov, U.A.; Nazir, S.

2009-04-01

We consider quadratic stochastic operators, which are separable as a product of two linear operators. Depending on properties of these linear operators we classify the set of the separable quadratic stochastic operators: first class of constant operators, second class of linear and third class of nonlinear (separable) quadratic stochastic operators. Since the properties of operators from the first and second classes are well known, we mainly study the properties of the operators of the third class. We describe some Lyapunov functions of the operators and apply them to study ω-limit sets of the trajectories generated by the operators. We also compare our results with known results of the theory of quadratic operators and give some open problems. (author)

THE MAIN PROBLEMS OF DEVELOPMENT OF LOGISTIC CENTERS IN RUSSIAN REGIONS

Directory of Open Access Journals (Sweden)

Sergey Kalenteev

2012-01-01

Full Text Available The article covers the problem of the formation of modern logistics centers in Russia: the absence of a common interpretation of the term "logistics center", the lack of legislative frameworks formation and operation of logistics infrastructure, the underestimation of the social significance of logistics centers. There are suggestions to set of measures to remove barriers to service quality logistics services in the article.

Operation Clean Feather: Reducing oil pollution in Newfoundland waters

International Nuclear Information System (INIS)

Chardine, J.W.; Pelly, G.

1994-01-01

Oil pollution of marine waters around Newfoundland, and particularly in the vicinity of Placentia Bay, is a frequent occurrence. Many oiled seabirds are found on beaches in the bay, particularly in winter. The most likely pollution sources are ship operators who dump waste oils from bilges and slop tanks. In an effort to reduce the chronic discharge of waste oil into Placentia Bay, and thus the incidence of bird oiling, Operation Clean Feather was launched in 1991-92 and consisted of weekly surveys of Placentia Bay beaches, sampling of oil from vessels using the bay and from oiled birds and beaches, and experimentation to determine possible recovery rates of birds oiled at sea. The operation was considered a success at a number of levels. Significant reductions in numbers of oiled birds were noted in both 1991 and 1992 compared to 1989 or 1990. Estimated oil-related mortality was reduced to ca 25% of levels seen in the two years prior to the operation. The operation also provided the opportunity to test and refine an organizational framework designed to deal with the problem of chronic oil pollution reports. Communication efforts heightened the awareness of the oil pollution problem in Newfoundland waters. These efforts included distribution of pamphlets in various languages to ship operators, describing the seriousness of oil-related marine bird mortality and warning of the substantial fines that can be imposed under the Canada Shipping Act. 6 refs., 3 figs., 1 tab

Obstacle mean-field game problem

KAUST Repository

Gomes, Diogo A.; Patrizi, Stefania

2015-01-01

In this paper, we introduce and study a first-order mean-field game obstacle problem. We examine the case of local dependence on the measure under assumptions that include both the logarithmic case and power-like nonlinearities. Since the obstacle operator is not differentiable, the equations for first-order mean field game problems have to be discussed carefully. Hence, we begin by considering a penalized problem. We prove this problem admits a unique solution satisfying uniform bounds. These bounds serve to pass to the limit in the penalized problem and to characterize the limiting equations. Finally, we prove uniqueness of solutions. © European Mathematical Society 2015.

To the confinement problem

International Nuclear Information System (INIS)

Savvidi, G.K.

1985-01-01

Such a viewpoint is proposed for separation of the physical quantities into observable and unobservable ones, when the latters are connected with the Hermitian operator for which the eigenvalue problem is unsolvable

W-algebra for solving problems with fuzzy parameters

Science.gov (United States)

Shevlyakov, A. O.; Matveev, M. G.

2018-03-01

A method of solving the problems with fuzzy parameters by means of a special algebraic structure is proposed. The structure defines its operations through operations on real numbers, which simplifies its use. It avoids deficiencies limiting applicability of the other known structures. Examples for solution of a quadratic equation, a system of linear equations and a network planning problem are given.

Development and application of a methodology for the analysis of significant human related event trends in nuclear power plants

International Nuclear Information System (INIS)

Cho, H.Y.

1981-01-01

A methodology is developed to identify and flag significant trends related to the safety and availability of U.S. commercial nuclear power plants. The development is intended to aid in reducing likelihood of human errors. To assure that the methodology can be easily adapted to various types of classification schemes of operation data, a data bank classified by the Transient Analysis Classification and Evaluation (TRACE) scheme is selected for the methodology. The significance criteria for human-initiated events affecting the systems and for events caused by human deficiencies were developed. Clustering analysis was used to verify the learning trend in multidimensional histograms. A computer code is developed based on the K-Means algorithm and applied to find the learning period in which error rates are monotonously decreasing with plant age. The Freeman-Tukey (F-T) deviates are used to select generic problems identified by a large positive value (here approximately over 2.0) for the deviate. The identified generic problems are: decision errors which are highly associated with reactor startup operations in the learning period of PWR plants (PWRs), response errors which are highly associated with Secondary Non-Nuclear Systems (SNS) in PWRs, and significant errors affecting systems and which are caused by response action are highly associated with startup reactor mode in BWRS

Spectral factorization using the delta operator

DEFF Research Database (Denmark)

Rostgaard, Morten; Poulsen, Niels Kjølstad; Ravn, Ole

1994-01-01

In recent years many papers have been published abouth the gamma-operator, mostly caused by the better numerical properties and the rapprochement between continuous and discrete time. A major problem within the LQG-design of a delta-based input-output relation has been how to spectral-factorize...... solution to the spectral factorization problem. The key idea is to use the gamma-operator resembled by its behavior to the differential operator....... in an efficient way. The discrete-time method of Kuccera will not be applied since numerical word-length characteristics will be poor for fast sampling rates. In this paper a new approach is considered. A new gamma-operator (Tustin operator) is introduced, in order to make an iterative and numerical stable...

Inverse resonance problems for the Schrödinger operator on the real line with mixed given data

Science.gov (United States)

Xu, Xiao-Chuan; Yang, Chuan-Fu

2018-01-01

In this work, we study inverse resonance problems for the Schrödinger operator on the real line with the potential supported in [0, 1]. In general, all eigenvalues and resonances cannot uniquely determine the potential. (i) It is shown that if the potential is known a priori on [0, 1 / 2], then the unique recovery of the potential on the whole interval from all eigenvalues and resonances is valid. (ii) If the potential is known a priori on [0, a], then for the case a>1/2, infinitely many eigenvalues and resonances can be missing for the unique determination of the potential, and for the case alogarithmic derivative values of eigenfunctions and wave-functions at 1 / 2, can uniquely determine the potential.

Some design and operating aspects of the Ranger uranium mine treatment plant

International Nuclear Information System (INIS)

Baily, P.A.

1984-01-01

Environmental considerations were key factors in the design of the Ranger Uranium Mines treatment plant. The mine is located adjacent to the Kakadu National Park and has an average rainfall of 1.6m per annum. No contaminated water or liquid effluents are to be released from the project area and thus water management is a key design and operating fact. Particulate and gas emission criteria influenced design as did occupational hygiene factors (dust, radon, housekeeping, maintenance access). Equipment selection and engineering standards were conservative and resulted in the plant attaining design performance in less than three months from the date of commissioning. A number of mechanical and operational problems were experienced. However, none of these problems have had a significant effect on production

The A-priori Traveling Salesman Problem with Time Windows

DEFF Research Database (Denmark)

Larsen, Allan; Madsen, Oli B.G.; Solomon, Marius M.

2004-01-01

seek to minimize lateness and examine the impact of this criterion choice on the distance traveled. Our focus on lateness is motivated by the problem faced by overnight mail service providers. We propose a real-time solution method that requires the vehicle, when idle, to wait at the current customer......In this paper we examine the traveling saleman problem with time windows for various degrees of dynamism. In contrast to the static problem, where the dispatcher can plan ahead, in the dynamic version, part or all of the necessary information becomes available only during the day of operation. We...... randomly generated data and on a real-world case study indicate that all policies proved capable of significantly reducing lateness. Our results also show that this can be accomplished with only small distance increases. The basic policy outperformed the other methods primarily when lateness and distance...

Non-LTE radiative transfer with lambda-acceleration - Convergence properties using exact full and diagonal lambda-operators

Science.gov (United States)

Macfarlane, J. J.

1992-01-01

We investigate the convergence properties of Lambda-acceleration methods for non-LTE radiative transfer problems in planar and spherical geometry. Matrix elements of the 'exact' A-operator are used to accelerate convergence to a solution in which both the radiative transfer and atomic rate equations are simultaneously satisfied. Convergence properties of two-level and multilevel atomic systems are investigated for methods using: (1) the complete Lambda-operator, and (2) the diagonal of the Lambda-operator. We find that the convergence properties for the method utilizing the complete Lambda-operator are significantly better than those of the diagonal Lambda-operator method, often reducing the number of iterations needed for convergence by a factor of between two and seven. However, the overall computational time required for large scale calculations - that is, those with many atomic levels and spatial zones - is typically a factor of a few larger for the complete Lambda-operator method, suggesting that the approach should be best applied to problems in which convergence is especially difficult.

Monitoring of the operation of a nuclear power station with design problems in an importing country: The Almaraz power station

International Nuclear Information System (INIS)

Reig, J.

1984-01-01

The purpose of this paper is to describe the regulatory activities carried out in Spain as a result of the design problem occurring in the steam generators during operation of Unit I of the Almaraz nuclear power station. First, a brief introduction is given to the operating history and characteristics of Unit I of Almaraz. Particular attention is paid to the specific licences issued subsequent to commercial operation which place limitations on the operation of the station and to the operational incidents of which the Nuclear Safety Council (CSN) has been notified. Next, a description is provided of the safety evaluation carried out by the CSN. Three aspects merit particular attention: methodology, evaluation and conclusions. The methodology applied by an importing country is normally based on that of the country of origin of the design, so that the overall evaluation by the NRC has been considered sufficiently representative of aspects specific to the Almaraz power station. In this regard the importance of international collaboration is clearly seen as a principal instrument for performing the evaluation. In the evaluation a distinction is made between general and specific aspects and between inspection programmes and quality assurance requirements. In addition, the conclusions leading to the requirement of the imposition of additional limitations on the operating licence are stated. Apart from the safety evaluation carried out by the CSN, other regulatory activities have been performed over this two-year period. These activities, which include site inspections, audits of the principal supplier company, other independent calculations and so on, are described. Lastly, the paper refers to the lessons learned from the operation of the above-mentioned unit, which are immediately applicable to other Spanish nuclear power stations. (author)

Erroneous analyses of interactions in neuroscience: a problem of significance

NARCIS (Netherlands)

Nieuwenhuis, S.; Forstmann, B.U.; Wagenmakers, E.-J.

2011-01-01

In theory, a comparison of two experimental effects requires a statistical test on their difference. In practice, this comparison is often based on an incorrect procedure involving two separate tests in which researchers conclude that effects differ when one effect is significant (P < 0.05) but the

Spectral computations for bounded operators

CERN Document Server

Ahues, Mario; Limaye, Balmohan

2001-01-01

Exact eigenvalues, eigenvectors, and principal vectors of operators with infinite dimensional ranges can rarely be found. Therefore, one must approximate such operators by finite rank operators, then solve the original eigenvalue problem approximately. Serving as both an outstanding text for graduate students and as a source of current results for research scientists, Spectral Computations for Bounded Operators addresses the issue of solving eigenvalue problems for operators on infinite dimensional spaces. From a review of classical spectral theory through concrete approximation techniques to finite dimensional situations that can be implemented on a computer, this volume illustrates the marriage of pure and applied mathematics. It contains a variety of recent developments, including a new type of approximation that encompasses a variety of approximation methods but is simple to verify in practice. It also suggests a new stopping criterion for the QR Method and outlines advances in both the iterative refineme...

Sample Size of One: Operational Qualitative Analysis in the Classroom

Directory of Open Access Journals (Sweden)

John Hoven

2015-10-01

Full Text Available Qualitative analysis has two extraordinary capabilities: first, finding answers to questions we are too clueless to ask; and second, causal inference – hypothesis testing and assessment – within a single unique context (sample size of one. These capabilities are broadly useful, and they are critically important in village-level civil-military operations. Company commanders need to learn quickly, "What are the problems and possibilities here and now, in this specific village? What happens if we do A, B, and C?" – and that is an ill-defined, one-of-a-kind problem. The U.S. Army's Eighty-Third Civil Affairs Battalion is our "first user" innovation partner in a new project to adapt qualitative research methods to an operational tempo and purpose. Our aim is to develop a simple, low-cost methodology and training program for local civil-military operations conducted by non-specialist conventional forces. Complementary to that, this paper focuses on some essential basics that can be implemented by college professors without significant cost, effort, or disruption.

Notes on human factors problems in process plant reliability and safety prediction

International Nuclear Information System (INIS)

Rasmussen, J.; Taylor, J.R.

1976-09-01

The basis for plant operator reliability evaluation is described. Principles for plant design, necessary to permit reliability evaluation, are outlined. Five approaches to the plant operator reliability problem are described. Case stories, illustrating operator reliability problems, are given. (author)

Introduction to operator space theory

CERN Document Server

Pisier, Gilles

2003-01-01

An introduction to the theory of operator spaces, emphasising examples that illustrate the theory and applications to C*-algebras, and applications to non self-adjoint operator algebras, and similarity problems. Postgraduate and professional mathematicians interested in functional analysis, operator algebras and theoretical physics will find the book has much to offer.

Unit-time scheduling problems with time dependent resources

NARCIS (Netherlands)

Tautenhahn, T.; Woeginger, G.

1997-01-01

We investigate the computational complexity of scheduling problems, where the operations consume certain amounts of renewable resources which are available in time-dependent quantities. In particular, we consider unit-time open shop problems and unit-time scheduling problems with identical parallel

Creativity and Problem Solving

DEFF Research Database (Denmark)

Vidal, Rene Victor Valqui

2004-01-01

This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving...... approach are also discussed. Finally, some applications of these concepts and tools are outlined. Some central references are presented for further study of themes related to creativity or creative tools....

Density operators in quantum mechanics

International Nuclear Information System (INIS)

Burzynski, A.

1979-01-01

A brief discussion and resume of density operator formalism in the way it occurs in modern physics (in quantum optics, quantum statistical physics, quantum theory of radiation) is presented. Particularly we emphasize the projection operator method, application of spectral theorems and superoperators formalism in operator Hilbert spaces (Hilbert-Schmidt type). The paper includes an appendix on direct sums and direct products of spaces and operators, and problems of reducibility for operator class by using the projection operators. (author)

Safety problems of nuclear power plants with channel-type graphite boiling water reactors

International Nuclear Information System (INIS)

Emel'yanov, I.Ya.; Vasilevskij, V.P.; Volkov, V.P.; Gavrilov, P.A.; Kramerov, A.Ya.; Kuznetsov, S.P.; Kunegin, E.P.; Rybakov, N.Z.

1977-01-01

Construction of nuclear power plants in a highly populated region near large industrial centres necessitates to pay a special attention to their nuclear and radiation safety. Safety problems of nuclear reactor operation are discussed, in particular, they are: reliable stoppage of fission chain reaction at any emergency cases; reliable core cooling with failure of various equipment; emergency core cooling with breached pipes of a circulating circuit; and prevention of radioactive coolant release outside the nuclear power plant in amount exceeding the values adopted. Channel-type water boiling reactors incorporate specific features requiring a new approach to safety operation of a reactor and a nuclear power plant. These include primarily a rather large steam volume in the coolant circuit, large amount of accumulated heat, void reactivity coefficient. Channel-type reactors characterized by fair neutron balance and flexible fuel cycle, have a series of advantages alleviating the problem of ensuring their safety. The possibility of reliable control over the state of each channel allows to replace failed fuel elements by the new ones, when operating on-load, to increase the number of circulating loops and reduce the diameter of main pipelines, simplifies significantly the problem of channel emergency cooling and localization of a radioactive coolant release from a breached circuit. The concept of channel-type reactors is based on the solution of three main problems. First, plant safety should be assured in emergency switch off of separate units and, if possible, energy conditions should be maintained, this is of particular importance considering the increase in unit power. Second, the system of safety and emergency cooling should eliminate a great many failures of fuel elements in case of potential breaches of any tube in the circulating circuit. Finally, rugged boxes and localizing devices should be provided to exclude damage of structural elements of the nuclear power

Formaldehyde OMI operational retrieval upgrades

Science.gov (United States)

Gonzalez Abad, G.; Chance, K.; Liu, X.

2013-05-01

Total column of formaldehyde (HCHO), a proxy for biogenic emissions, can be observed from satellites using the ultraviolet region of the spectrum. The operational HCHO retrievals from the Ozone Monitoring Instrument (OMI) on board the AURA satellite, part of NASA's A-train constellation of Earth Observing satellites, are described. The operational retrieval, based on a basic optical absorption spectroscopy (BOAS) algorithm, has been affected by the degradation of the instrument especially from 2008 onwards. The most significant problems are the unrealistic increasing high background concentrations of HCHO retrieved from OMI and the row anomaly. An upgrade for the original operational algorithm is therefore needed to ensure its trend quality and to account for these difficulties. The strategies implemented to deal with the instrumental degradation are presented here. Air mass factors (AMFs) in the current fitting window show significant wavelength dependence. Fitting uncertainties can potentially be improved by including shorter wavelengths as long as the AMFs wavelength dependence is taken into account. As part of these improvements a look-up table of wavelength-dependent AMFs have been calculated. Using this new table it is possible to retrieve the HCHO total column directly, weighting the HCHO cross sections with the wavelength-dependent AMFs. Additionally, the pixels affected by the row anomaly are now flagged in the level 2 data generated with the upgraded algorithm.

Clinically significant discrepancies between sleep problems assessed by standard clinical tools and actigraphy

Directory of Open Access Journals (Sweden)

Kjersti Marie Blytt

2017-10-01

Full Text Available Abstract Background Sleep disturbances are widespread among nursing home (NH patients and associated with numerous negative consequences. Identifying and treating them should therefore be of high clinical priority. No prior studies have investigated the degree to which sleep disturbances as detected by actigraphy and by the sleep-related items in the Cornell Scale for Depression in Dementia (CSDD and the Neuropsychiatric Inventory – Nursing Home version (NPI-NH provide comparable results. Such knowledge is highly needed, since both questionnaires are used in clinical settings and studies use the NPI-NH sleep item to measure sleep disturbances. For this reason, insight into their relative (disadvantages is valuable. Method Cross-sectional study of 83 NH patients. Sleep was objectively measured with actigraphy for 7 days, and rated by NH staff with the sleep items in the CSDD and the NPI-NH, and results were compared. McNemar's tests were conducted to investigate whether there were significant differences between the pairs of relevant measures. Cohen's Kappa tests were used to investigate the degree of agreement between the pairs of relevant actigraphy, NPI-NH and CSDD measures. Sensitivity and specificity analyses were conducted for each of the pairs, and receiver operating characteristics (ROC curves were designed as a plot of the true positive rate against the false positive rate for the diagnostic test. Results Proxy-raters reported sleep disturbances in 20.5% of patients assessed with NPI-NH and 18.1% (difficulty falling asleep, 43.4% (multiple awakenings and 3.6% (early morning awakenings of patients had sleep disturbances assessed with CSDD. Our results showed significant differences (p<0.001 between actigraphy measures and proxy-rated sleep by the NPI-NH and CSDD. Sensitivity and specificity analyses supported these results. Conclusions Compared to actigraphy, proxy-raters clearly underreported NH patients' sleep disturbances as assessed

Operator approach to linear control systems

CERN Document Server

Cheremensky, A

1996-01-01

Within the framework of the optimization problem for linear control systems with quadratic performance index (LQP), the operator approach allows the construction of a systems theory including a number of particular infinite-dimensional optimization problems with hardly visible concreteness. This approach yields interesting interpretations of these problems and more effective feedback design methods. This book is unique in its emphasis on developing methods for solving a sufficiently general LQP. Although this is complex material, the theory developed here is built on transparent and relatively simple principles, and readers with less experience in the field of operator theory will find enough material to give them a good overview of the current state of LQP theory and its applications. Audience: Graduate students and researchers in the fields of mathematical systems theory, operator theory, cybernetics, and control systems.

A New Result Concerning the Solvability of a Class of General Systems of Variational Equations with Nonmonotone Operators: Applications to Dirichlet and Neumann Nonlinear Problems

Directory of Open Access Journals (Sweden)

Luisa Toscano

2016-01-01

Full Text Available A new result of solvability for a wide class of systems of variational equations depending on parameters and governed by nonmonotone operators is found in a Banach real and reflexive space with applications to Dirichlet and Neumann problems related to nonlinear elliptic systems.

Exponential operations and aggregation operators of interval neutrosophic sets and their decision making methods.

Science.gov (United States)

Ye, Jun

2016-01-01

An interval neutrosophic set (INS) is a subclass of a neutrosophic set and a generalization of an interval-valued intuitionistic fuzzy set, and then the characteristics of INS are independently described by the interval numbers of its truth-membership, indeterminacy-membership, and falsity-membership degrees. However, the exponential parameters (weights) of all the existing exponential operational laws of INSs and the corresponding exponential aggregation operators are crisp values in interval neutrosophic decision making problems. As a supplement, this paper firstly introduces new exponential operational laws of INSs, where the bases are crisp values or interval numbers and the exponents are interval neutrosophic numbers (INNs), which are basic elements in INSs. Then, we propose an interval neutrosophic weighted exponential aggregation (INWEA) operator and a dual interval neutrosophic weighted exponential aggregation (DINWEA) operator based on these exponential operational laws and introduce comparative methods based on cosine measure functions for INNs and dual INNs. Further, we develop decision-making methods based on the INWEA and DINWEA operators. Finally, a practical example on the selecting problem of global suppliers is provided to illustrate the applicability and rationality of the proposed methods.

Optimization methods for the Train Unit Shunting Problem

DEFF Research Database (Denmark)

Haahr, Jørgen Thorlund; Lusby, Richard Martin; Wagenaar, Joris Camiel

2017-01-01

We consider the Train Unit Shunting Problem, an important planning problem for passenger railway operators. This problem entails assigning train units from shunting yards to scheduled train services in such a way that the resulting operations are without conflicts. The problem arises at every...... shunting yard in the railway network and involves matching train units to arriving and departing train services as well as assigning the selected matchings to appropriate shunting yard tracks. We present an extensive comparison benchmark of multiple solution approaches for this problem, some of which...... are novel. In particular, we develop a constraint programming formulation, a column generation approach, and a randomized greedy heuristic. We compare and benchmark these approaches with two existing methods, a mixed integer linear program and a two-stage heuristic. The benchmark contains multiple real...

Green functions of vortex operators

International Nuclear Information System (INIS)

Polchinski, J.; California Univ., Berkeley

1981-01-01

We study the euclidean Green functions of the 't Hooft vortex operator, primarly for abelian gauge theories. The operator is written in terms of elementary fields, with emphasis on a form in which it appears as the exponential of a surface integral. We explore the requirement that the Green functions depend only on the boundary of this surface. The Dirac veto problem appears in a new guise. We present a two-dimensional solvable model of a Dirac string, which suggests a new solution of the veto problem. The renormalization of the Green functions of the abelian Wilson loop and abelian vortex operator is studied with the aid of the operator product expansion. In each case, an overall multiplication of the operator makes all Green functions finite; a surprising cancellation of divergences occurs with the vortex operator. We present a brief discussion of the relation between the nature of the vacuum and the cluster properties of the Green functions of the Wilson and vortex operators, for a general gauge theory. The surface-like cluster property of the vortex operator in an abelian Higgs theory is explored in more detail. (orig.)

A Schwarz alternating procedure for singular perturbation problems

Energy Technology Data Exchange (ETDEWEB)

Garbey, M. [Universit Claude Bernard Lyon, Villeurbanne (France); Kaper, H.G. [Argonne National Lab., IL (United States)

1994-12-31

The authors show that the Schwarz alternating procedure offers a good algorithm for the numerical solution of singular perturbation problems, provided the domain decomposition is properly designed to resolve the boundary and transition layers. They give sharp estimates for the optimal position of the domain boundaries and present convergence rates of the algorithm for various second-order singular perturbation problems. The splitting of the operator is domain-dependent, and the iterative solution of each subproblem is based on a modified asymptotic expansion of the operator. They show that this asymptotic-induced method leads to a family of efficient massively parallel algorithms and report on implementation results for a turning-point problem and a combustion problem.

Fundamental problem in the relativistic approach to atomic structure theory

International Nuclear Information System (INIS)

Kagawa, Takashi

1987-01-01

It is known that the relativistic atomic structure theory contains a serious fundamental problem, so-called the Brown-Ravenhall (BR) problem or variational collapse. This problem arises from the fact that the energy spectrum of the relativistic Hamiltonian for many-electron systems is not bounded from below because the negative-energy solutions as well as the positive-energy ones are obtained from the relativistic equation. This report outlines two methods to avoid the BR problem in the relativistic calculation, that is, the projection operator method and the general variation method. The former method is described first. The use of a modified Hamiltonian containing a projection operator which projects the positive-energy solutions in the relativistic wave equation has been proposed to remove the BR difficulty. The problem in the use of the projection operator method is that the projection operator for the system cannot be determined uniquely. The final part of this report outlines the general variation method. This method can be applied to any system, such as relativistic ones whose Hamiltonian is not bounded from below. (Nogami, K.)

Operational exposition and analysis of the inverse problem electroencephalographic; Planteamiento operacional y analisis del problema inverso electroencefalografico

Energy Technology Data Exchange (ETDEWEB)

Fraguela Collar, Andres; Oliveros Oliveros, Jose J.; Ivanovich Grebennikov, Alexandre [Benemerita Universidad Autonoma de Puebla, Puebla (Mexico)

2001-04-01

Techniques of the potential theory have been used to analyze the properties of the operator where the sources of current produced by electric activity in the cerebral cortex is associated with the measurements on the scalp of the electric potential generated by these sources. A medium conductor model which take in account the circle convolution of the brain has been used to prove the uniqueness of solution of the inverse problem of recuperation of activity cortical sources from electroencephalographic measurement on the scalp. This result of uniqueness is very important because we can to use algorithms of regularization. An other state the problem is presented to elaborate numerical solutions of the inverse problem using a set of discrete measurement. The stability of algorithms is showed in some examples. [Spanish] Tecnicas de la teoria de potencial han sido utilizadas para analizar las propiedades del operador que a las fuentes de corriente asociadas a la actividad electrica de las neuronas en la corteza cerebral, le hace corresponder la medicion de potencial electrico generado por dichas fuentes sobre el cuero cabelludo. Un modelo de medio conductor que toma en consideracion las circonvoluciones del cerebro ha sido utilizado para probar la unidad de solucion del problema inverso de recuperacion de las fuentes de actividad cortical a partir de las mediciones electroencefalograficas. Este resultado de unidad es fundamental ya que nos permite aplicar los metodos de regularizacion. Es presentado otro planteamiento del problema que nos permite construir soluciones numericas del problema inverso usando los datos de entrada discretos. La estabilidad de los algoritmos es ilustrada en algunos ejemplos numericos.

Estimating meme fitness in adaptive memetic algorithms for combinatorial problems.

Science.gov (United States)

Smith, J E

2012-01-01

Among the most promising and active research areas in heuristic optimisation is the field of adaptive memetic algorithms (AMAs). These gain much of their reported robustness by adapting the probability with which each of a set of local improvement operators is applied, according to an estimate of their current value to the search process. This paper addresses the issue of how the current value should be estimated. Assuming the estimate occurs over several applications of a meme, we consider whether the extreme or mean improvements should be used, and whether this aggregation should be global, or local to some part of the solution space. To investigate these issues, we use the well-established COMA framework that coevolves the specification of a population of memes (representing different local search algorithms) alongside a population of candidate solutions to the problem at hand. Two very different memetic algorithms are considered: the first using adaptive operator pursuit to adjust the probabilities of applying a fixed set of memes, and a second which applies genetic operators to dynamically adapt and create memes and their functional definitions. For the latter, especially on combinatorial problems, credit assignment mechanisms based on historical records, or on notions of landscape locality, will have limited application, and it is necessary to estimate the value of a meme via some form of sampling. The results on a set of binary encoded combinatorial problems show that both methods are very effective, and that for some problems it is necessary to use thousands of variables in order to tease apart the differences between different reward schemes. However, for both memetic algorithms, a significant pattern emerges that reward based on mean improvement is better than that based on extreme improvement. This contradicts recent findings from adapting the parameters of operators involved in global evolutionary search. The results also show that local reward schemes

A posteriori error analysis of multiscale operator decomposition methods for multiphysics models

International Nuclear Information System (INIS)

Estep, D; Carey, V; Tavener, S; Ginting, V; Wildey, T

2008-01-01

Multiphysics, multiscale models present significant challenges in computing accurate solutions and for estimating the error in information computed from numerical solutions. In this paper, we describe recent advances in extending the techniques of a posteriori error analysis to multiscale operator decomposition solution methods. While the particulars of the analysis vary considerably with the problem, several key ideas underlie a general approach being developed to treat operator decomposition multiscale methods. We explain these ideas in the context of three specific examples

Unbounded weighted composition operators in L²-spaces

CERN Document Server

Budzyński, Piotr; Jung, Il Bong; Stochel, Jan

2018-01-01

This book establishes the foundations of the theory of bounded and unbounded weighted composition operators in L²-spaces. It develops the theory in full generality, meaning that the weighted composition operators under consideration are not regarded as products of multiplication and composition operators. A variety of seminormality properties are characterized and the first-ever criteria for subnormality of unbounded weighted composition operators is provided. The subtle interplay between the classical moment problem, graph theory and the injectivity problem is revealed and there is an investigation of the relationships between weighted composition operators and the corresponding multiplication and composition operators. The optimality of the obtained results is illustrated by a variety of examples, including those of discrete and continuous types. The book is primarily aimed at researchers in single or multivariable operator theory.

Deterministic operations research models and methods in linear optimization

CERN Document Server

Rader, David J

2013-01-01

Uniquely blends mathematical theory and algorithm design for understanding and modeling real-world problems Optimization modeling and algorithms are key components to problem-solving across various fields of research, from operations research and mathematics to computer science and engineering. Addressing the importance of the algorithm design process. Deterministic Operations Research focuses on the design of solution methods for both continuous and discrete linear optimization problems. The result is a clear-cut resource for understanding three cornerstones of deterministic operations resear

The benefits and challenges of sharing glidein factory operations across nine time zones between OSG and CMS

Science.gov (United States)

Sfiligoi, I.; Dost, J. M.; Zvada, M.; Butenas, I.; Holzman, B.; Wuerthwein, F.; Kreuzer, P.; Teige, S. W.; Quick, R.; Hernández, J. M.; Flix, J.

2012-12-01

OSG has been operating for a few years at UCSD a glideinWMS factory for several scientific communities, including CMS analysis, HCC and GLOW. This setup worked fine, but it had become a single point of failure. OSG thus recently added another instance at Indiana University, serving the same user communities. Similarly, CMS has been operating a glidein factory dedicated to reprocessing activities at Fermilab, with similar results. Recently, CMS decided to host another glidein factory at CERN, to increase the availability of the system, both for analysis, MC and reprocessing jobs. Given the large overlap between this new factory and the three factories in the US, and given that CMS represents a significant fraction of glideins going through the OSG factories, CMS and OSG formed a common operations team that operates all of the above factories. The reasoning behind this arrangement is that most operational issues stem from Grid-related problems, and are very similar for all the factory instances. Solving a problem in one instance thus very often solves the problem for all of them. This paper presents the operational experience of how we address both the social and technical issues of running multiple instances of a glideinWMS factory with operations staff spanning multiple time zones on two continents.

A DE-Based Scatter Search for Global Optimization Problems

Directory of Open Access Journals (Sweden)

Kun Li

2015-01-01

Full Text Available This paper proposes a hybrid scatter search (SS algorithm for continuous global optimization problems by incorporating the evolution mechanism of differential evolution (DE into the reference set updated procedure of SS to act as the new solution generation method. This hybrid algorithm is called a DE-based SS (SSDE algorithm. Since different kinds of mutation operators of DE have been proposed in the literature and they have shown different search abilities for different kinds of problems, four traditional mutation operators are adopted in the hybrid SSDE algorithm. To adaptively select the mutation operator that is most appropriate to the current problem, an adaptive mechanism for the candidate mutation operators is developed. In addition, to enhance the exploration ability of SSDE, a reinitialization method is adopted to create a new population and subsequently construct a new reference set whenever the search process of SSDE is trapped in local optimum. Computational experiments on benchmark problems show that the proposed SSDE is competitive or superior to some state-of-the-art algorithms in the literature.

Modeling visual problem solving as analogical reasoning.

Science.gov (United States)

Lovett, Andrew; Forbus, Kenneth

2017-01-01

We present a computational model of visual problem solving, designed to solve problems from the Raven's Progressive Matrices intelligence test. The model builds on the claim that analogical reasoning lies at the heart of visual problem solving, and intelligence more broadly. Images are compared via structure mapping, aligning the common relational structure in 2 images to identify commonalities and differences. These commonalities or differences can themselves be reified and used as the input for future comparisons. When images fail to align, the model dynamically rerepresents them to facilitate the comparison. In our analysis, we find that the model matches adult human performance on the Standard Progressive Matrices test, and that problems which are difficult for the model are also difficult for people. Furthermore, we show that model operations involving abstraction and rerepresentation are particularly difficult for people, suggesting that these operations may be critical for performing visual problem solving, and reasoning more generally, at the highest level. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

On-line determination of operating limits incorporating constraint costs and reliability assessment

International Nuclear Information System (INIS)

Meisingset, M.; Lovas, G. G.

1997-01-01

Problems regarding power system operation following deregulation were discussed. The problems arise as a result of the increased power flow pattern created by deregulation and competitive power markets, resulting in power in excess of N-1, (the capacity of transmission lines available), which in turn creates bottlenecks. In a situation like this, constraint costs and security costs (i.e. the cost of supply interruptions) are incurred as the direct result of the deterministic criteria used in reliability assessment. This paper describes an on-line probabilistic method to determine operating limits based on a trade-off between constraint costs and security costs. The probability of the contingencies depend on the existing weather conditions, which therefore has significant impact on the calculated operating limit. In consequence, the proposed method allows power flow to exceed the N-1 limit during normal weather. Under adverse weather conditions the N-1 criteria should be maintained. 15 refs., 13 figs

Psychological factors of professional success of nuclear power plant main control room operators

Directory of Open Access Journals (Sweden)

Kosenkov A.A.

2014-12-01

Full Text Available Aim: to conduct a comparative analysis of the psychological characteristics of the most and least successful main control room operators. Material and Methods. Two NPP staff groups: the most and least successful main control room operators, who worked in routine operating conditions, were surveyed. Expert evaluation method has been applied to identify the groups. The subjects were administered the Minnesota Multiphasic Personality Inventory (MMPI, Cattell's Sixteen Personality Factor Questionnaire (16PF form A and Raven's Progressive Matrices test. Results. Numerous significant psychological differences between the groups of most and least successful control room operators were obtained: the best operators were significantly more introverted and correctly solved more logical tasks with smaller percentage of mistakes under time pressure than worst ones. Conclusions: 1. The psychodiagnostic methods used in the study were adequate to meet research objective 2. Tendency to introversion, as well as developed the ability to solve logic problems undertime pressure, apparently, are important professional qualities for control room operators. These indicators should be considered in the process of psychological selection and professional guidance of nuclear power plant operators.

Homogenization of variational inequalities for obstacle problems

International Nuclear Information System (INIS)

Sandrakov, G V

2005-01-01

Results on the convergence of solutions of variational inequalities for obstacle problems are proved. The variational inequalities are defined by a non-linear monotone operator of the second order with periodic rapidly oscillating coefficients and a sequence of functions characterizing the obstacles. Two-scale and macroscale (homogenized) limiting variational inequalities are obtained. Derivation methods for such inequalities are presented. Connections between the limiting variational inequalities and two-scale and macroscale minimization problems are established in the case of potential operators.

Classification of ξ(s)-Quadratic Stochastic Operators on 2D simplex

International Nuclear Information System (INIS)

Mukhamedov, Farrukh; Saburov, Mansoor; Qaralleh, Izzat

2013-01-01

A quadratic stochastic operator (in short QSO) is usually used to present the time evolution of differing species in biology. Some QSO has been studied by Lotka and Volterra. The general problem in the nonlinear operator theory is to study the behavior of operators. This problem was not fully finished even for the quadratic stochastic operators. To study this problem it was investigated several classes of such QSO. In this paper we study ξ (s) -QSO class of operators. We study such kind of operators on 2D simplex. We first classify these ξ (s) -QSO into 20 classes. Further, we investigate the dynamics of one class of such operators.

Operating Theatre Planning and Scheduling.

NARCIS (Netherlands)

Hans, Elias W.; Vanberkel, P.T.; Hall, R.

2012-01-01

In this chapter we present a number of approaches to operating theatre planning and scheduling. We organize these approaches hierarchically which serves to illustrate the breadth of problems confronted by researchers. At each hierarchicalplanning level we describe common problems, solution

Trace formulas for parameter-dependent pseudodifferential operators

DEFF Research Database (Denmark)

Grubb, Gerd

2002-01-01

Trace expansions for operator families such as the resolvent, the heat operator and the complex powers are established for elliptic problems containing pseudodifferential elements. We consider operators on closed manifolds, as well as operators on compact manifolds with boundary, where suitable...

Kozloduy NPP units 1-4 significance for Bulgaria

International Nuclear Information System (INIS)

Georgiev, J.

2003-01-01

General data about nuclear power in Bulgaria is presented. The main topics covered are: estimated energy reserve; energy balance, new capacities, installed in 2002; information about the WWER-230 reactors operation; environmental impact and global warming; Bulgarian export and regional electricity demand; public opinion etc. The problem 'Long term safe operation vs forced early closure' is discussed. It is concluded that the decision on early closure of any unit should be made on economic grounds or failure to meet regulatory safety standards and must not be politically motivated

Creativity and problem Solving

Directory of Open Access Journals (Sweden)

René Victor Valqui Vidal

2004-12-01

Full Text Available This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving approach are also discussed. Finally, some applications of these concepts and tools are outlined. Some central references are presented for further study of themes related to creativity or creative tools.

SEP operating history of the Dresden Nuclear Power Station Unit 2

International Nuclear Information System (INIS)

Mays, G.T.; Harrington, K.H.

1983-01-01

206 forced shutdowns and power reductions were reviewed, along with 631 reportable events and other miscellaneous documentation concerning the operation of Dresden-2, in order to indicate those areas of plant operation that compromised plant safety. The most serious plant challenge to plant safety occurred on June 5, 1970; while undergoing power testing at 75% power, a spurious signal in the reactor pressure control system caused a turbine trip followed by a reactor scram. Subsequent erratic water level and pressure control in the reactor vessel, compounded by a stuck indicator pen on a water level monitor-recorder and inability of the isolation condenser to function, led to discharge of steam and water through safety valves into the reactor drywell. No significant contamination was discharged. There was no pressure damage or the reactor vessel of the drywell containment walls. Six areas of operation that should be of continued concern are diesel generator failures, control rod and rod drive malfunctions, radioactive waste management/health physics program problems, operator errors, turbine control valve and EHC problems, and HPCI failures. All six event types have continued to recur

Dynamic Vehicle Routing Problems with Enhanced Ant Colony Optimization

Directory of Open Access Journals (Sweden)

Haitao Xu

2018-01-01

Full Text Available As we all know, there are a great number of optimization problems in the world. One of the relatively complicated and high-level problems is the vehicle routing problem (VRP. Dynamic vehicle routing problem (DVRP is a major variant of VRP, and it is closer to real logistic scene. In DVRP, the customers’ demands appear with time, and the unserved customers’ points must be updated and rearranged while carrying out the programming paths. Owing to the complexity and significance of the problem, DVRP applications have grabbed the attention of researchers in the past two decades. In this paper, we have two main contributions to solving DVRP. Firstly, DVRP is solved with enhanced Ant Colony Optimization (E-ACO, which is the traditional Ant Colony Optimization (ACO fusing improved K-means and crossover operation. K-means can divide the region with the most reasonable distance, while ACO using crossover is applied to extend search space and avoid falling into local optimum prematurely. Secondly, several new evaluation benchmarks are proposed, which can objectively and comprehensively estimate the proposed method. In the experiment, the results for different scale problems are compared to those of previously published papers. Experimental results show that the algorithm is feasible and efficient.

Verification and validation--The key to operating plant software reliability

International Nuclear Information System (INIS)

Daughtrey, H.T.; Daggett, P.W.; Schamp, C.A.

1983-01-01

This paper discusses the design and implementation of a verification and validation (V and V) plan for reviewing the microcomputer software developed for a Safety Parameter Display System (SPDS). Topics considered include a historical perspective on V and V, the function and significance of SPDS software, and testing. An SPDS provides information to nuclear power plant operators about the status of the plant under all operating conditions. It is determined that by implementing V and V activities throughout the development cycle, problems are less expensive to locate in the early phases of software development, problems are less expensive to fix in the early phases of software development, and a parallel V and V activity is more cost effective than a similar effort performed only at the end of software development. It is concluded that V and V is a proven tool for improving power plant software reliability

Talking to your parents about emotional problems

Science.gov (United States)

... regarding government operating status and resumption of normal operations can be found at https://www.opm.gov/ . Section navigation Your feelings: Being happy Could I have a mental health problem? Feeling sad Having body image issues ...

On the singular Sturm-Liouville problems that have the same spectrum

Energy Technology Data Exchange (ETDEWEB)

Gulsen, Tuba [Department of Mathematics, Firat University, 23119, Elazig (Turkey); Ulusoy, Ismail [Department of Mathematics, Adiyaman University, 02040,Adiyaman (Turkey)

2016-06-08

The problem of efficaciously constucting the potential q (x) and the numbers h and H was solved in [1]. Trubowitz [2] investigated the isospectrality problem which have the same spectrum with other same type of problems. Then Jodeit and Levitan [3] considered this problem with a different approach, based on transmutation operators and integral equation. In this work, we discussed this problem for singular Sturm-Liouville operator and obtained some important formulas for the number H, the potential q (x) and the norming constants α{sub n}.

System theoretic approach to sustainable development problems

Directory of Open Access Journals (Sweden)

Batanović Vladan

2011-01-01

Full Text Available This paper shows that the concepts and methodology contained in the system theory and operations research are suitable for application in the planning and control of the sustainable development. The sustainable development problems can be represented using the state space concepts, such as the transition of system, from the given initial state to the final state. It is shown that sustainable development represents a specific control problem. The peculiarity of the sustainable development is that the target is to keep the system in the prescribed feasible region of the state space. The analysis of planning and control problems of sustainable development has also shown that methods developed in the operations research area, such as multicriteria optimization, dynamic processes simulation, non-conventional treatment of uncertainty etc. are adequate, exact base, suitable for resolution of these problems.

Closed nuclear facilities in Estonia: developments and problems

International Nuclear Information System (INIS)

Realo, E.; Realo, K.

2000-01-01

At present Estonia has no operating nuclear or a radioactive material production facility. As a legacy of the past the country has become responsible for the decommissioning of two large nuclear cycle facilities of the former USSR. Besides limited funding, major problems arise from deficiencies in legislation, expertise, training and research. International co-operation has been of immense importance to overcome the problems, to establish the national radiation protection and radioactive waste management infrastructure and to launch decommissioning and remediation activities. An overview is given on the status and problems. Copyright (2000) Australasian Radiation Protection Society Inc

Problems in fluid flow

International Nuclear Information System (INIS)

Brasch, D.J.

1986-01-01

Chemical and mineral engineering students require texts which give guidance to problem solving to complement their main theoretical texts. This book has a broad coverage of the fluid flow problems which these students may encounter. The fundamental concepts and the application of the behaviour of liquids and gases in unit operation are dealt with. The book is intended to give numerical practice; development of theory is undertaken only when elaboration of treatments available in theoretical texts is absolutely necessary

Solving inversion problems with neural networks

Science.gov (United States)

Kamgar-Parsi, Behzad; Gualtieri, J. A.

1990-01-01

A class of inverse problems in remote sensing can be characterized by Q = F(x), where F is a nonlinear and noninvertible (or hard to invert) operator, and the objective is to infer the unknowns, x, from the observed quantities, Q. Since the number of observations is usually greater than the number of unknowns, these problems are formulated as optimization problems, which can be solved by a variety of techniques. The feasibility of neural networks for solving such problems is presently investigated. As an example, the problem of finding the atmospheric ozone profile from measured ultraviolet radiances is studied.

Applying an Evidence-Based Assessment Model to Identify Students at Risk for Perceived Academic Problems following Concussion.

Science.gov (United States)

Ransom, Danielle M; Burns, Alison R; Youngstrom, Eric A; Vaughan, Christopher G; Sady, Maegan D; Gioia, Gerard A

2016-11-01

The aim of this study was to demonstrate the utility of an evidence-based assessment (EBA) model to establish a multimodal set of tools for identifying students at risk for perceived post-injury academic problems. Participants included 142 students diagnosed with concussion (age: M=14.95; SD=1.80; 59% male), evaluated within 4 weeks of injury (median=16 days). Demographics, pre-injury history, self- and parent-report measures assessing symptom severity and executive functions, and cognitive test performance were examined as predictors of self-reported post-injury academic problems. Latent class analysis categorized participants into "high" (44%) and "low" (56%) levels of self-reported academic problems. Receiver operating characteristic analyses revealed significant discriminative validity for self- and parent-reported symptom severity and executive dysfunction and self-reported exertional response for identifying students reporting low versus high academic problems. Parent-reported symptom ratings [area under the receiver operating characteristic curve (AUC)=.79] and executive dysfunction (AUC=.74), and self-reported ratings of executive dysfunction (AUC=.84), symptoms (AUC=.80), and exertional response (AUC=.70) each classified students significantly better than chance (psperspective in the management of concussion by applying traditional strengths of neuropsychological assessment to clinical decision making. (JINS, 2016, 22, 1038-1049).

Severe accidents and operator training - discussion of potential issues

International Nuclear Information System (INIS)

Vidard, Michel

1997-01-01

R and D programs developed throughout the world allowed significant progress in the understanding of physical phenomena and Severe Accident Management (SAM) programs started in many OECD countries. Basically, the common denominator to all these SAM programs was to provide utility operators with procedures or guidelines allowing to deal with complex situations not formally considered in the Design Basis, including accidents where a significant portion of the core had molten. These SAM procedures or guidelines complement the traditional accident management procedures (event, symptom or physical-state oriented) and should allow operators to deal with a reasonably bounding set of situations. Dealing with operator or crisis team training, it was recognized that training would be beneficial but that training programs were lagging, i.e. though training sessions were either organized or contemplated after implementation of SAM programs, they seemed to be somewhat different from more traditional training sessions on Accident Management. After some explanations on the differences between Design Basis Accidents (DBAs) and Beyond Design Basis Accidents (BDBAs), this paper underlines some potential difficulties for training operators and discuss problems to be addressed by organisms contemplating SAM training sessions consistent with similar activities for less complex events

Alpha: A real-time decentralized operating system for mission-oriented system integration and operation

Science.gov (United States)

Jensen, E. Douglas

1988-01-01

Alpha is a new kind of operating system that is unique in two highly significant ways. First, it is decentralized transparently providing reliable resource management across physically dispersed nodes, so that distributed applications programming can be done largely as though it were centralized. And second, it provides comprehensive, high technology support for real-time system integration and operation, an application area which consists predominately of aperiodic activities having critical time constraints such as deadlines. Alpha is extremely adaptable so that it can be easily optimized for a wide range of problem-specific functionality, performance, and cost. Alpha is the first systems effort of the Archons Project, and the prototype was created at Carnegie-Mellon University directly on modified Sun multiprocessor workstation hardware. It has been demonstrated with a real-time C(sup 2) application. Continuing research is leading to a series of enhanced follow-ons to Alpha; these are portable but initially hosted on Concurrent's MASSCOMP line of multiprocessor products.

Managing for nuclear operational effectiveness

International Nuclear Information System (INIS)

Nevins, P.A.; Kasperski, D.C.

1990-01-01

The nuclear energy industry worldwide is changing, with significant implications for nuclear utility managers. While the UK and US nuclear industries have many differences, a number of the lessons learned in the US have direct applicability to the UK. Just as the physics behind nuclear power transcends political boundaries, so do many of the management techniques that are necessary to run an efficient and sound operation. The US nuclear industry is no longer a construction-based industry, as it has been for years. As nuclear construction slows or stops in many parts of the world and nuclear power comes under increased scrutiny everywhere, the industry is shifting away from a construction emphasis and towards an operations and maintenance emphasis. In North America more than one-half of nuclear executives believe that plant operating and maintenance costs, and not construction-related problems, are their number one concern. Furthermore, when asked what actions they would expect to take as a result of this concern, the majority indicated that the actions would be management-related for the most part, and included items such as: emphasize operating improvements, emphasize management improvements, upgrade outage management and maintenance management programs, increase senior management involvement and set management performance criteria. (author)

Statistical factors affecting the success of nuclear operations

International Nuclear Information System (INIS)

Sunder, S.; Stephenson, J.R.; Hochman, D.

1999-01-01

In this article, the authors present a statistical analysis to determine the operational, financial, technical, and managerial factors that most significantly affect the success of nuclear operations. The study analyzes data for over 70 nuclear plants and 40 operating companies over a period of five years in order to draw conclusions that they hope will be of interest to utility companies and public utility commissions as they seek ways to improve rates of success in nuclear operations. Some of these conclusions will not be surprising--for example, that older plants have heavier maintenance requirements--but others are less intuitive. For instance, the observation that operators of fewer plants have lower costs suggests that any experience curve benefits associated with managing multiple nuclear facilities is overshadowed by the logistic problems of multiple facilities. After presenting a brief history of nuclear power in America, the authors outline the motivations of the study and the methodology of their analysis. They end the article with the results of the study and discuss some of the managerial implications of these findings

TRIGA reactor operating experience

International Nuclear Information System (INIS)

Anderson, T.V.

1970-01-01

The Oregon State TRIGA Reactor (OSTR) has been in operation 3 years. Last August it was upgraded from 250 kW to 1000 kW. This was accomplished with little difficulty. During the 3 years of operation no major problems have been experienced. Most of the problems have been minor in nature and easily corrected. They came from lazy susan (dry bearing), Westronics Recorder (dead spots in the range), The Reg Rod Magnet Lead-in Circuit (a new type lead-in wire that does not require the lead-in cord to coil during rod withdrawal hss been delivered, much better than the original) and other small corrections

The searchlight problem for neutrons in a semi-infinite medium

International Nuclear Information System (INIS)

Ganapol, B.D.

1993-01-01

The solution of the Search Light Problem for monoenergetic neutrons in a semi-infinite medium with isotropic scattering illuminated at the free surface is obtained by several methods at various planes within the medium. The sources considered are a normally-incident pencil beam and an isotropic point source. The analytic solution is effected by a recently developed numerical inversion technique applied to the Fourier-Bessel transform. This transform inversion results from the solution method of Rybicki, where the two-dimensional problem is solved by casting it as a variant of a one-dimensional problem. The numerical inversion process results in a highly accurate solution. Comparisons of the analytic solution with results from Monte Carlo (MCNP) and discrete ordinates transport (DORT) codes show excellent agreement. These comparisons, which are free of any associated data or cross section set dependencies, provide significant evidence of the proper operation of both the transport codes tested

Operator interface programs for KSTAR operation

International Nuclear Information System (INIS)

Lee, Sangil; Park, Mikyung; Park, Jinseop; Na, Hoonkyun; Kwon, M.

2013-01-01

Beginning the first plasma discharging experiment of KSTAR since 2008, KSTAR performed the third plasma discharging experiment by 2010. During the experiment of three times, KSTAR OPerator Interface (OPI) programs have been developed for KSTAR operation by itself. OPI programs used in KSTAR were implemented by KSTAR widget plug-in Toolkit (KWT). The KWT means the plug-in library implemented by Qt-based user interface development software. The main purpose of developing the KWT library is to implement full automation libraries having interface with the automated EPICS channel access (CA) guaranteeing the flexibility for requirements of operators. In addition, it has advantages in minimizing human code error and maximizing utilization of the limited human resource. According to the increasing of control systems, a number of OPI servers connected to one EPICS gateway server caused the connection problem and increased the amount of the network data packets. To solve these problems, an algorithm of “CachedChannelAccess” for shared memory base was implemented into an inner logic of the KWT library. KSTAR control system monitoring (CSM) program is one of applications developed by using KWT library. The function of CSM program is to notify alarm to operators by checking health status of every server's network health status and resource (cpu, memory, network packets, disk usage rate and system/user defined process) usage state. Another application is a post-shot sequencing program which is activated after every shot is completed. This application is to display major plasma parameters and diagnostic data in chart form, to save this data to database, and to transfer a chart image file to a web server. This paper describes the technical details how to develop OPI applications which have high productivity using Qt on the EPICS-based control system

Operator interface programs for KSTAR operation

Energy Technology Data Exchange (ETDEWEB)

Lee, Sangil, E-mail: leesi@nfri.re.kr; Park, Mikyung, E-mail: mkpark@nfri.re.kr; Park, Jinseop, E-mail: linupark@nfri.re.kr; Na, Hoonkyun, E-mail: hkna@nfri.re.kr; Kwon, M., E-mail: kwonm@nfri.re.kr

2013-11-15

Beginning the first plasma discharging experiment of KSTAR since 2008, KSTAR performed the third plasma discharging experiment by 2010. During the experiment of three times, KSTAR OPerator Interface (OPI) programs have been developed for KSTAR operation by itself. OPI programs used in KSTAR were implemented by KSTAR widget plug-in Toolkit (KWT). The KWT means the plug-in library implemented by Qt-based user interface development software. The main purpose of developing the KWT library is to implement full automation libraries having interface with the automated EPICS channel access (CA) guaranteeing the flexibility for requirements of operators. In addition, it has advantages in minimizing human code error and maximizing utilization of the limited human resource. According to the increasing of control systems, a number of OPI servers connected to one EPICS gateway server caused the connection problem and increased the amount of the network data packets. To solve these problems, an algorithm of “CachedChannelAccess” for shared memory base was implemented into an inner logic of the KWT library. KSTAR control system monitoring (CSM) program is one of applications developed by using KWT library. The function of CSM program is to notify alarm to operators by checking health status of every server's network health status and resource (cpu, memory, network packets, disk usage rate and system/user defined process) usage state. Another application is a post-shot sequencing program which is activated after every shot is completed. This application is to display major plasma parameters and diagnostic data in chart form, to save this data to database, and to transfer a chart image file to a web server. This paper describes the technical details how to develop OPI applications which have high productivity using Qt on the EPICS-based control system.

Modified and fuzzified general problem solver for 'monkey and banana' problem

International Nuclear Information System (INIS)

Sano, Norihide; Takahashi, Ryoichi.

1994-01-01

Automatic operation is important for the in-service inspection of nuclear power stations of the decommission of retired plants. Master and slave control will be introduced for work-robot control. It is desirable that the slave possess problem-solving capabilities. In this paper we assume that the slave incorporates the general problem solver (GPS) algorithm. In view of having solved the 'monkey and banana' problem, the slave system is regarded as reasonable alternative which incorporates the capability of problem-solving. Basically, the GPS solves a problem by reducing the difference between the initial state and goal state, and hence the performance of GPS depends on selection of the difference to be reduced. The conventional GPS is given the order of importance of the differences in advance. In this study, the GPS was improved by making use of the rules which determine the order. When several choices are available for the given difference, a fuzzified decision to determine the necessary action is made, as demonstrated in this paper. (author)

A Unifying Framework for the Problem of Adjudicating Conflicting Claims

DEFF Research Database (Denmark)

Hougaard, Jens Leth; Moreno-Ternero, Juan D.; Østerdal, Lars Peter Raahave

the structure of such a space. In this paper, we generalize their analysis upon presenting and studying a general family of operators inspired by three apparently unrelated approaches to the problem of adjudicating conflicting claims. We study the structural properties of this family and show, in particular......In a recent paper, Thomson and Yeh [Operators for the adjudication of conflicting claims, Journal of Economic Theory 143 (2008) 177-198] introduced the concept of operators on the space of rules for the problem of adjudicating conflicting claims. They focussed on three operators in order to uncover...

A physiological exploration on operational stance and occupational musculoskeletal problem manifestations amongst construction labourers of West Bengal, India.

Science.gov (United States)

Chatterjee, Arijit; Sahu, Subhashis

2018-03-29

A huge number of labourers engaged in construction industry in India both in organized and unorganized sectors. The construction labourers most often work for an extended period of time and they are compelled to uphold altered static and dynamic operational stance in awkward positions during the complete period of work which raises the demand on the musculoskeletal system and may lead to work related musculoskeletal disorders (WRMSDs). This study is intended to explore the operational stance and occupation related musculoskeletal manifestations amongst the construction labourers. One sixty four male labourers from different construction sites of West Bengal was randomly taken for this study. A modified Nordic questionnaire on MSD and the 12 item General Health Questionnaire (GHQ12) were administered on the construction labourers. Rapid Entire Body Assessment [REBA] and Ovako Work Analysis System [OWAS] methods were applied to analyze the operational stance. Finally, discomfort levels of the specific operational stance were calculated by the use of risk level and BPD scale. From the study it was revealed that most of the construction labourers habitually in awkward operational stance and were affected by altering musculoskeletal manifestations like pain in low back, neck, and wrist. It has been also found that there is a significant (pconstruction labourers in unorganized sectors.

Main animal welfare problems in ruminant livestock during preslaughter operations: a South American view.

Science.gov (United States)

Gallo, C B; Huertas, S M

2016-02-01

Animals destined for meat production are usually exposed to many stressful conditions during production and particularly during preslaughter operations. Handling animals on farm, loading into and unloading from vehicles, transportation, passing through livestock markets, fasting, lairage and stunning can all affect their welfare. How badly welfare can be affected will depend on both the intrinsic factors of the specific type of animal involved and the extrinsic factors of the environment where those animals live or are being handled, including the animal handlers. In South America (SA), it has been part of a strategy for improving animal welfare (AW) to address not only ethical aspects, but to emphasize the close relationship existing between handling ruminants preslaughter and the quantity and quality of the meat they produce. This has resulted not only in improvements in AW, but has also brought economic rewards to producers which in turn can lead to higher incomes for them and hence better human welfare. For producers with a high number of animals, considering AW during production and preslaughter operations can determine the possibility of exporting and/or getting better prices for their products. At smallfarmer level, particularly in some less developed countries, where human welfare is impaired, using this strategy together with education has also been relevant. It is important that education and training in AW are done not only considering global knowledge, but also including specific geographical and climatic characteristics of each country and the cultural, religious and socio-economical characteristics of its people; therefore, research within the context of each country or region becomes relevant. The aim of this review was to show the results of research dealing with AW of ruminant livestock in Chile and some other SA countries. Some of the main problems encountered are related to lack of proper infrastructure to handle animals; long distance transport

EXTEND OPERATION PROBLEMS AND RECONSTRUCTION OF LARGEPANEL FIVE-STOREY BUILDINGS OF 50-60-IES XX CENTURY

Directory of Open Access Journals (Sweden)

BOLSHAKOV V. I.,

2016-01-01

. Thus, the continued exploatation of large five-storey buildings today is a big problem that requires a consistent scientific basis and achievements of mechanisms to solve it. On the construction industry lie the tasks of different nature: technological (development projects and successful design solutions for reconstruction, heat and sound insulation of residential buildings, a significant decrease in the heat capacity of the wall surfaces of concrete panels, economic (creation and selection of economic viable options of reconstruction, reducing the cost of the work, social and legal (housing quality improvement in compliance with regulatory requirements and legislative support. In the aspect of these tasks is an interesting study of foreign experience (eg, Germany, Poland, Czech Republic, the reconstruction of five-story building. On these and other questions will be directed our further research.

Duoplasmatron source modifications for 3He+ operation

Science.gov (United States)

Schmidt, C. W.; Popovic, M.

1998-02-01

A duoplasmatron ion source is used to produce 25 mA of 3He+ with a pulse width of ˜80 ms at 360 Hz for acceleration to 10.5 MeV. At this energy, 3He striking water or carbon targets can produce short lived isotopes of 11C, 13N, 15O, and 18F for medical positron emission tomography (PET). A duoplasmatron ion source was chosen originally since it is capable of a sufficient singly charged helium beam with an acceptable gas consumption. Stable long-term operation of the source required a change in the filament material to molybdenum, and a careful understanding of the oxide filament conditioning, operation and geometry. Other improvements, particularly in the electronics, were helpful to increasing the reliability. The source has operated for many months at ˜2.5% duty factor without significant problems and with good stability. We report here the effort that was done to make this source understandable and reliable.

Duoplasmatron source modifications for 3He+ Operation

International Nuclear Information System (INIS)

Schmidt, C.W.; Popovic, M.

1997-11-01

A duoplasmatron ion source is used to produce 25 mA of 3 He+ with a pulse width of ∼80 ms at 360 Hz for acceleration to 10.5 MeV. At this energy, 3 He striking water or carbon targets can produce short lived isotopes of 11 C, 13 N, 15 O and 18 F for medical positron emission tomography (PET). A duoplasmatron ion source was chosen originally since it is capable of a sufficient singly-charged helium beam with an acceptable gas consumption. Stable long-term operation of the source required a change in the filament material to molybdenum, and a careful understanding of the oxide filament conditioning, operation and geometry. Other improvements, particularly in the electronics, were helpful to increasing the reliability. The source has operated for many months at ∼2.5% duty factor without significant problems and with good stability. We report here the effort that was done to make this source understandable and reliable

Duoplasmatron source modifications for 3He+ operation

International Nuclear Information System (INIS)

Schmidt, C.W.; Popovic, M.

1998-01-01

A duoplasmatron ion source is used to produce 25 mA of 3 He + with a pulse width of ∼80ms at 360 Hz for acceleration to 10.5 MeV. At this energy, 3 He striking water or carbon targets can produce short lived isotopes of 11 C, 13 N, 15 O, and 18 F for medical positron emission tomography (PET). A duoplasmatron ion source was chosen originally since it is capable of a sufficient singly charged helium beam with an acceptable gas consumption. Stable long-term operation of the source required a change in the filament material to molybdenum, and a careful understanding of the oxide filament conditioning, operation and geometry. Other improvements, particularly in the electronics, were helpful to increasing the reliability. The source has operated for many months at ∼2.5% duty factor without significant problems and with good stability. We report here the effort that was done to make this source understandable and reliable

When the asymptotic limit offers no advantage in the local-operations-and-classical-communication paradigm

Science.gov (United States)

Fu, Honghao; Leung, Debbie; Mančinska, Laura

2014-05-01

We consider bipartite LOCC, the class of operations implementable by local quantum operations and classical communication between two parties. Surprisingly, there are operations that can be approximated to arbitrary precision but are impossible to implement exactly if only a finite number of messages are exchanged. This significantly complicates the analysis of what can or cannot be approximated with LOCC. Toward alleviating this problem, we exhibit two scenarios in which allowing vanishing error does not help. The first scenario is implementation of projective measurements with product measurement operators. The second scenario is the discrimination of unextendable product bases on two three-dimensional systems.

Feedback from peer review missions of the self-assessment of operational events reflecting safety culture (Leningrad, Smolemsk and Balakovo NPP's, the Russian Federation)

International Nuclear Information System (INIS)

Gantchev, T.

1997-01-01

The presentation discusses the following issues: criteria for reporting events inside NPP; screening of the plant operational events; third safety culture indicator; list of the pending safety problems; significance of the safety problems for plant reliability; prioritization of the safety culture issues. Tabs

The Joint Master Operational Planner

Science.gov (United States)

2016-04-04

enable commanders to understand the strategic-operational environment and make sound decisions. Current PME and JPME systems attempt to keep pace, but...SAASS, MAWS, SAW), which provides them with a deeper understanding of operational art and science, problem solving, and planning. These programs...to translate new understanding into sound planning methodologies that follow, to include development of operational approaches and campaign plans

Modifications needed to operate PWR's plants in G-Mode

International Nuclear Information System (INIS)

Stainman, J.P.

1985-01-01

The production of electricity from PWR nuclear plants represents 44% of the total production of electricity in France for 1984, and 68% of the electricity produced by Thermal power plants (127 TWh over 187 TWh). These data show clearly that the French PWR plants do not work in ''base mode'' anymore but have to fit production with consumption, in other words to assume the frequency control. To participate permanently to the load follow and frequency control, it appeared that some improvements in the field of pressurizer level and pressure control were necessary as well as in the field of operator aids computer. It should be noted that these improvements are useful even without taking into account the constraints due to load follow and frequency control because of the mechanical stress in the CVCS piping, for instance. Some additional tests are planned to better identify this specific problem. The need of a more flexible operating mode than ones given by the initial system (black control rods), significantly reduced in 1973 due to the application of the ECCS criterion, led EDF and Framatome to develop a new operating mode (G. Mode) allowing a faster power escalation (5% PN/mn) whatever the fuel burn-up. This new operating mode improves significantly also the flexibility of operation when the frequency control is needed, and helps a lot the operators in such cases. All the 900 MWe Nuclear plants will be able to operate in ''G mode'' before the end of 1984

Shippingport operations with the Light Water Breeder Reactor core. (LWBR Development Program)

International Nuclear Information System (INIS)

Budd, W.A.

1986-03-01

This report describes the operation of the Shippingport Atomic Power Station during the LWBR (Light Water Breeder Reactor) Core lifetime. It also summarizes the plant-oriented operations during the period preceding LWBR startup, which include the defueling of The Pressurized Water Reactor Core 2 (PWR-2) and the installation of the LWBR Core, and the operations associated with the defueling of LWBR. The intent of this report is to examine LWBR experience in retrospect and present pertinent and significant aspects of LWBR operations that relate primarily to the nuclear portion of the Station. The nonnuclear portion of the Station is discussed only as it relates to overall plant operation or to unusual problems which result from the use of conventional equipment in radioactive environments. 30 refs., 69 figs., 27 tabs

Scattering theory some old and new problems

CERN Document Server

Yafaev, Dmitri R

2000-01-01

Scattering theory is, roughly speaking, perturbation theory of self-adjoint operators on the (absolutely) continuous spectrum. It has its origin in mathematical problems of quantum mechanics and is intimately related to the theory of partial differential equations. Some recently solved problems, such as asymptotic completeness for the Schrödinger operator with long-range and multiparticle potentials, as well as open problems, are discussed. Potentials for which asymptotic completeness is violated are also constructed. This corresponds to a new class of asymptotic solutions of the time-dependent Schrödinger equation. Special attention is paid to the properties of the scattering matrix, which is the main observable of the theory. The book is addressed to readers interested in a deeper study of the subject.

Safety significance evaluation system

International Nuclear Information System (INIS)

Lew, B.S.; Yee, D.; Brewer, W.K.; Quattro, P.J.; Kirby, K.D.

1991-01-01

This paper reports that the Pacific Gas and Electric Company (PG and E), in cooperation with ABZ, Incorporated and Science Applications International Corporation (SAIC), investigated the use of artificial intelligence-based programming techniques to assist utility personnel in regulatory compliance problems. The result of this investigation is that artificial intelligence-based programming techniques can successfully be applied to this problem. To demonstrate this, a general methodology was developed and several prototype systems based on this methodology were developed. The prototypes address U.S. Nuclear Regulatory Commission (NRC) event reportability requirements, technical specification compliance based on plant equipment status, and quality assurance assistance. This collection of prototype modules is named the safety significance evaluation system

Some problems in operator theory on bounded symmetric domains

Czech Academy of Sciences Publication Activity Database

Engliš, Miroslav

2004-01-01

Roč. 81, č. 1 (2004), s. 51-71 ISSN 0167-8019. [Representations of Lie groups, harmonic analysis on homogeneous spaces and quantization. Leiden, 07.12.2002-13.12.2002] R&D Projects: GA ČR GA201/03/0041 Institutional research plan: CEZ:AV0Z1019905 Keywords : homogeneous multiplication operators * bounded symmetric domains Subject RIV: BA - General Mathematics Impact factor: 0.354, year: 2004

Perturbation analysis of linear control problems

International Nuclear Information System (INIS)

Petkov, Petko; Konstantinov, Mihail

2017-01-01

The paper presents a brief overview of the technique of splitting operators, proposed by the authors and intended for perturbation analysis of control problems involving unitary and orthogonal matrices. Combined with the technique of Lyapunov majorants and the implementation of the Banach and Schauder fixed point principles, it allows to obtain rigorous non-local perturbation bounds for a set of sensitivity analysis problems. Among them are the reduction of linear systems into orthogonal canonical forms, the feedback synthesis problem and pole assignment problem in particular, as well as other important problems in control theory and linear algebra. Key words: perturbation analysis, canonical forms, feedback synthesis

Problem gambling and drinking among Finnish women

Directory of Open Access Journals (Sweden)

Järvinen-Tassopoulos Johanna

2016-02-01

Full Text Available AIM - This qualitative study expands on female problem gambling by examining short online narratives written by Finnish women. Problem gambling is analysed within the familial context in order to discover gendered roles and practices, and in relation to substance use and abuse in women’s lives. DESIGN - Two sets of qualitative data were used in this study. The first set was collected from two online discussion forums, and the second set was extracted from an online counselling service data in 2008. Chosen messages formed short narratives of women’s problem gambling trajectory (51 cases. The data were analysed in accordance with the content analysis method. RESULTS - Women had started gambling either in adolescence or in adulthood. Most of the women played on slot machines or gambled online. The lack of coping skills, stressful events in life and troubled relationships made the women more vulnerable to gambling harms and other addictions. In some couples, partners were either drinking or gambling. This made the women’s lives even more complicated, because they could not count on their partners’ help and support. The women tried to hide the consequences of their problem gambling for fear of losing their significant others. CONCLUSIONS - Female gambling and female problem gambling are complex concepts influenced by social, cultural and political factors. This study has shown in its limited framework that female problem gambling is related to the gambling environment, the social acceptance of gambling and the regulation of gambling operations within the place of jurisdiction.

Disc operational system

International Nuclear Information System (INIS)

Veretenov, V.Yu.; Volkov, A.I.; Gurevich, M.I.; Kozik, V.S.; Pod'yachev, E.I.; Shapiro, M.L.

1974-01-01

A disc operational system is proposed, which is based on the file structure and designed for use in a BESM-6 computer with the software system comprising a dispatcher DD-73 and a monitor 'Dubna'. The main distinguishing feature of the disc operational system is the decentralization of the file system. Each disc package is an independent file unaffected by the state of the other disc packages. The use of several disc packages is allowed. The above feature of the disc operational system makes it possible to simplify the language of communication with the system, to give the user the opportunity of controlling the file quite independently, and to simplify the maintenance of the discs by the computer personnel. One and the same disc can be simultaneously addressed by all problems in the processor (both mathematical and service). A single file, however, may be used in the recording mode by only one problem. The description presented is the instruction for users. It also describes special possibilities open to the system programmers [ru

Nuclear energy; real problems of the long term development

International Nuclear Information System (INIS)

Knapp, V.

1996-01-01

Whilst general public accepts the operation of western designed nuclear power stations as safe, waste management and decommission still figure as open problems, although such views are not in agreement with technical and economic status of these operations. A concern with imagined problems can have the effect of neglecting the real ones. In considering the long term development of nuclear energy the real problems can be associated with the wide use of plutonium and multiplication of national reprocessing and enrichment installations. Nuclear proliferation safety could be retained and developed through establishment of international nuclear fuel centres. Their operation would be particularly beneficial for small or medium nuclear countries. Several arguments are given why it is not premature to initiate a study which would identify and analyze the problems of establishing an international nuclear fuel centre. Central Europe could be a region which could be served by one of such nuclear fuel centres. (author)

Operations Research Games : A Survey

NARCIS (Netherlands)

Borm, P.E.M.; Hamers, H.J.M.; Hendrickx, R.L.P.