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Sample records for techniques solve metalworking

  1. An evaluation of analytical methods, air sampling techniques, and airborne occupational exposure of metalworking fluids.

    Science.gov (United States)

    Verma, Dave K; Shaw, Don S; Shaw, M Lorraine; Julian, Jim A; McCollin, Shari-Ann; des Tombe, Karen

    2006-02-01

    This article summarizes an assessment of air sampling and analytical methods for both oil and water-based metalworking fluids (MWFs). Three hundred and seventy-four long-term area and personal airborne samples were collected at four plants using total (closed-face) aerosol samplers and thoracic samplers. A direct-reading device (DustTrak) was also used. The processes sampled include steel tube making, automotive component manufacturing, and small part manufacturing in a machine shop. The American Society for Testing and Materials (ASTM) Method PS42-97 of analysis was evaluated in the laboratory. This evaluation included sample recovery, determination of detection limits, and stability of samples during storage. Results of the laboratory validation showed (a) the sample recovery to be about 87%, (b) the detection limit to be 35 microg, and (c) sample stability during storage at room temperature to decline rapidly within a few days. To minimize sample loss, the samples should be stored in a freezer and analyzed within a week. The ASTM method should be the preferred method for assessing metalworking fluids (MWFs). The ratio of thoracic aerosol to total aerosol ranged from 0.6 to 0.7. A similar relationship was found between the thoracic extractable aerosol and total extractable aerosol. The DustTrak, with 10-microm sampling head, was useful in pinpointing the areas of potential exposure. MWF exposure at the four plants ranged from 0.04 to 3.84 mg/m3 with the geometric mean ranging between 0.22 to 0.59 mg/m3. Based on this data and the assumption of log normality, MWF exposures are expected to exceed the National Institute for Occupational Safety and Health recommended exposure limit of 0.5 mg/m3 as total mass and 0.4 mg/m3 as thoracic mass about 38% of the time. In addition to controlling airborne MWF exposure, full protection of workers would require the institution of programs for fluid management and dermal exposure prevention.

  2. Crime Solving Techniques: Training Bulletin.

    Science.gov (United States)

    Sands, Jack M.

    The document is a training bulletin for criminal investigators, explaining the use of probability, logic, lateral thinking, group problem solving, and psychological profiles as methods of solving crimes. One chpater of several pages is devoted to each of the five methods. The use of each method is explained; problems are presented for the user to…

  3. Laser beam diagnostics for metalworking applications

    International Nuclear Information System (INIS)

    Ramos, T.J.; Lingenfelter, A.C.

    1984-01-01

    The Materials Fabrication Division of Lawrence Livermore National Laboratory (LLNL) has three pulsed Nd-YAG lasers dedicated to metalworking. The units are used in a job shop primarily for welding. They also have a number of applications requiring cutting and drilling capability. Each of these metalworking operations requires somewhat different laser beam characteristics. As most investigators have found, the mode of the laser beam and the mode stability are the key variables which must be controlled if optimum results are to be achieved. The authors use several techniques to observe and measure these variables, i.e. Charge Couple Device (CCD) Camera, Thermal Image Plate and thermal-sensitive paper

  4. A Versatile Technique for Solving Quintic Equations

    Science.gov (United States)

    Kulkarni, Raghavendra G.

    2006-01-01

    In this paper we present a versatile technique to solve several types of solvable quintic equations. In the technique described here, the given quintic is first converted to a sextic equation by adding a root, and the resulting sextic equation is decomposed into two cubic polynomials as factors in a novel fashion. The resultant cubic equations are…

  5. Metalworking and machining fluids

    Science.gov (United States)

    Erdemir, Ali; Sykora, Frank; Dorbeck, Mark

    2010-10-12

    Improved boron-based metal working and machining fluids. Boric acid and boron-based additives that, when mixed with certain carrier fluids, such as water, cellulose and/or cellulose derivatives, polyhydric alcohol, polyalkylene glycol, polyvinyl alcohol, starch, dextrin, in solid and/or solvated forms result in improved metalworking and machining of metallic work pieces. Fluids manufactured with boric acid or boron-based additives effectively reduce friction, prevent galling and severe wear problems on cutting and forming tools.

  6. A new technique for solving puzzles.

    Science.gov (United States)

    Makridis, Michael; Papamarkos, Nikos

    2010-06-01

    This paper proposes a new technique for solving jigsaw puzzles. The novelty of the proposed technique is that it provides an automatic jigsaw puzzle solution without any initial restriction about the shape of pieces, the number of neighbor pieces, etc. The proposed technique uses both curve- and color-matching similarity features. A recurrent procedure is applied, which compares and merges puzzle pieces in pairs, until the original puzzle image is reformed. Geometrical and color features are extracted on the characteristic points (CPs) of the puzzle pieces. CPs, which can be considered as high curvature points, are detected by a rotationally invariant corner detection algorithm. The features which are associated with color are provided by applying a color reduction technique using the Kohonen self-organized feature map. Finally, a postprocessing stage checks and corrects the relative position between puzzle pieces to improve the quality of the resulting image. Experimental results prove the efficiency of the proposed technique, which can be further extended to deal with even more complex jigsaw puzzle problems.

  7. 7 CFR 2902.41 - Metalworking fluids.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Metalworking fluids. 2902.41 Section 2902.41... Items § 2902.41 Metalworking fluids. (a) Definition. (1) Fluids that are designed to provide cooling... operations such as cutting, drilling, grinding, machining, and tapping. (2) Metalworking fluids for which...

  8. Solving fault diagnosis problems linear synthesis techniques

    CERN Document Server

    Varga, Andreas

    2017-01-01

    This book addresses fault detection and isolation topics from a computational perspective. Unlike most existing literature, it bridges the gap between the existing well-developed theoretical results and the realm of reliable computational synthesis procedures. The model-based approach to fault detection and diagnosis has been the subject of ongoing research for the past few decades. While the theoretical aspects of fault diagnosis on the basis of linear models are well understood, most of the computational methods proposed for the synthesis of fault detection and isolation filters are not satisfactory from a numerical standpoint. Several features make this book unique in the fault detection literature: Solution of standard synthesis problems in the most general setting, for both continuous- and discrete-time systems, regardless of whether they are proper or not; consequently, the proposed synthesis procedures can solve a specific problem whenever a solution exists Emphasis on the best numerical algorithms to ...

  9. Problem-Solving Techniques in the Management of Conflicts among ...

    African Journals Online (AJOL)

    Specifically, the findings also revealed that there is a significant relationship between skills acquired in problem-solving techniques and conflict management among rural dwellers. It is therefore recommended that conflict management, peace promotion and consolidation should involve a behavioural code, confidence ...

  10. Solving Systems of Equations with Techniques from Artificial Intelligence

    Directory of Open Access Journals (Sweden)

    Irina Maria Terfaloaga

    2015-07-01

    Full Text Available A frequent problem in numerical analysis is solving the systems of equations. That problem has generated in time a great interest among mathematicians and computer scientists, as evidenced by the large number of numerical methods developed. Besides the classical numerical methods, in the last years were proposed methods inspired by techniques from artificial intelligence. Hybrid methods have been also proposed along the time [15, 19]. The goal of this study is to make a survey of methods inspired from artificial intelligence for solving systems of equations

  11. 15 CFR 700.31 - Metalworking machines.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Metalworking machines. 700.31 Section 700.31 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE NATIONAL SECURITY INDUSTRIAL BASE REGULATIONS...

  12. Mamluk metalwork fittings in their artistic and architectural context

    NARCIS (Netherlands)

    Mols, Luitgard Eva Maria

    2006-01-01

    This study of Mamluk metalwork fittings presents a hitherto largely ignored body of Mamluk metalwork objects, i.e. metal-faced doors, doorknockers, window grilles, and window shutters, and aims to trace their stylistic and technical development throughout the Mamluk period. In order to establish the

  13. Emotional freedom techniques (EFT) and solving conflicts in third grade

    OpenAIRE

    Omahna, Tina

    2013-01-01

    Pedagogic work involves many areas including conflict resolution. Teachers and students resolve them in many different ways by using various techniques. One of them is also Emotional Freedom Technique or EFT that can be used in the process of resolving numerous emotional and physical problems. Gary Craig, the founder of the EFT, believes when using this technique or, more specifically, when we simultaneously tap on acupuncture points on our body with our fingers and tell our problems, we get ...

  14. Applying recursive numerical integration techniques for solving high dimensional integrals

    Energy Technology Data Exchange (ETDEWEB)

    Ammon, Andreas [IVU Traffic Technologies AG, Berlin (Germany); Genz, Alan [Washington State Univ., Pullman, WA (United States). Dept. of Mathematics; Hartung, Tobias [King' s College, London (United Kingdom). Dept. of Mathematics; Jansen, Karl; Volmer, Julia [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Leoevey, Hernan [Humboldt Univ. Berlin (Germany). Inst. fuer Mathematik

    2016-11-15

    The error scaling for Markov-Chain Monte Carlo techniques (MCMC) with N samples behaves like 1/√(N). This scaling makes it often very time intensive to reduce the error of computed observables, in particular for applications in lattice QCD. It is therefore highly desirable to have alternative methods at hand which show an improved error scaling. One candidate for such an alternative integration technique is the method of recursive numerical integration (RNI). The basic idea of this method is to use an efficient low-dimensional quadrature rule (usually of Gaussian type) and apply it iteratively to integrate over high-dimensional observables and Boltzmann weights. We present the application of such an algorithm to the topological rotor and the anharmonic oscillator and compare the error scaling to MCMC results. In particular, we demonstrate that the RNI technique shows an error scaling in the number of integration points m that is at least exponential.

  15. Applying recursive numerical integration techniques for solving high dimensional integrals

    International Nuclear Information System (INIS)

    Ammon, Andreas; Genz, Alan; Hartung, Tobias; Jansen, Karl; Volmer, Julia; Leoevey, Hernan

    2016-11-01

    The error scaling for Markov-Chain Monte Carlo techniques (MCMC) with N samples behaves like 1/√(N). This scaling makes it often very time intensive to reduce the error of computed observables, in particular for applications in lattice QCD. It is therefore highly desirable to have alternative methods at hand which show an improved error scaling. One candidate for such an alternative integration technique is the method of recursive numerical integration (RNI). The basic idea of this method is to use an efficient low-dimensional quadrature rule (usually of Gaussian type) and apply it iteratively to integrate over high-dimensional observables and Boltzmann weights. We present the application of such an algorithm to the topological rotor and the anharmonic oscillator and compare the error scaling to MCMC results. In particular, we demonstrate that the RNI technique shows an error scaling in the number of integration points m that is at least exponential.

  16. An efficient technique to solve combined economic and emission ...

    Indian Academy of Sciences (India)

    Owing to strict governmental regulations on environment protection, the traditional techniques at absolute minimum fuel cost cannot be the only foundation for dispatching ..... The transition probability is a trade-off between visibility (which says that process should be chosen with high probability, thus implementing a greedy ...

  17. METHOD FOR SOLVING FUZZY ASSIGNMENT PROBLEM USING MAGNITUDE RANKING TECHNIQUE

    OpenAIRE

    D. Selvi; R. Queen Mary; G. Velammal

    2017-01-01

    Assignment problems have various applications in the real world because of their wide applicability in industry, commerce, management science, etc. Traditional classical assignment problems cannot be successfully used for real life problem, hence the use of fuzzy assignment problems is more appropriate. In this paper, the fuzzy assignment problem is formulated to crisp assignment problem using Magnitude Ranking technique and Hungarian method has been applied to find an optimal solution. The N...

  18. Solving conformal contacts using multi-Hertzian techniques

    Science.gov (United States)

    Pascal, Jean-Pierre; Soua, Brahim

    2016-06-01

    Recently, publications aiming at wheel-rail contact surveys let readers think that multi-Hertzian methods present severe drawbacks with respect to 'virtual penetration' methods. These surveys criticise multi-Hertzian solutions mainly because presenting 'larger contacts overlaps' and 'frequent secondary contacts near the border of the first contact', both obvious geometric possibilities of which the practical occurrence and eventual inconvenience would remain purely theoretical unless established over definite methods demonstrating poor practical results. Recent surveys all quote Piotrowski-Chollet 2005 survey of wheel-rail contact models that attempted to illustrate defective multi-Hertzian techniques by concentrating on the method initiated by Sauvage in the 1990s and further developed by Pascal. The 2005 paper not only gives no evidence of practical inconveniences of Sauvage's method but also confuses static geometric contact overlaps with the dynamical overlapping of forces. In reality it mixes Sauvage method up with a quite different technique. Thus a clarification is now necessary by reminding what the proper Sauvage technique really is and by showing some of its practical successful applications. The present paper, focusing on determination of normal contact forces in conformal situations, intends to explain clearly the advantages of the unequivocal localisation of secondary ellipses in that multi-Hertzian method which has been developed in INRETS VOCO codes in the 1990s and successfully used by SNCF and ALSTOM in the INRETS-SNCF code, VOCODYM, and later in Pascal's online calculation of railway elastic contacts code. It proved its effectiveness for studying freight wagons derailments as well as rail wear and head-check, unrounded wheels wear, high-speed lines' deformations or TGV comfort. While simulating American ACELA trainsets' behaviour on the US North-East Corridor tracks, prior to actual tests, as part of the commercial contract. It has been also a

  19. A new iterative heuristic to solve the joint replenishment problem using a spreadsheet technique

    NARCIS (Netherlands)

    Nilsson, A.; Segerstedt, A.; van der Sluis, E.

    2007-01-01

    In this paper, a heuristic method is presented which gives a novel approach to solve joint replenishment problems (JRP) with strict cycle policies. The heuristic solves the JRP in an iterative procedure and is based on a spreadsheet technique. The principle of the recursion procedure is to find a

  20. Vaporization and Conversion of Ethanolamines used in Metalworking Operations

    Directory of Open Access Journals (Sweden)

    Shin-bum Kim

    2010-12-01

    Conclusion: MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

  1. An efficient numerical technique for solving navier-stokes equations for rotating flows

    International Nuclear Information System (INIS)

    Haroon, T.; Shah, T.M.

    2000-01-01

    This paper simulates an industrial problem by solving compressible Navier-Stokes equations. The time-consuming tri-angularization process of a large-banded matrix, performed by memory economical Frontal Technique. This scheme successfully reduces the time for I/O operations even for as large as (40, 000 x 40, 000) matrix. Previously, this industrial problem can solved by using modified Newton's method with Gaussian elimination technique for the large matrix. In the present paper, the proposed Frontal Technique is successfully used, together with Newton's method, to solve compressible Navier-Stokes equations for rotating cylinders. By using the Frontal Technique, the method gives the solution within reasonably acceptance computational time. Results are compared with the earlier works done, and found computationally very efficient. Some features of the solution are reported here for the rotating machines. (author)

  2. Solving Inverse Kinematics – A New Approach to the Extended Jacobian Technique

    Directory of Open Access Journals (Sweden)

    M. Šoch

    2005-01-01

    Full Text Available This paper presents a brief summary of current numerical algorithms for solving the Inverse Kinematics problem. Then a new approach based on the Extended Jacobian technique is compared with the current Jacobian Inversion method. The presented method is intended for use in the field of computer graphics for animation of articulated structures. 

  3. UV disinfection of soluble oil metalworking fluids.

    Science.gov (United States)

    Johnson, David L; Phillips, Margaret L

    2002-01-01

    The efficacy of a new high-intensity germicidal ultraviolet (UV) lamp for disinfection of opaque metalworking fluids (MWF) was investigated under laboratory conditions. Three dilutions of "soluble oil" MWF and water controls in a circulating system were inoculated with suspensions of Pseudomonas fluorescens to an initial concentration of about 10(7) colony forming units (CFU) per milliliter and irradiated with a submerged nonglass UV lamp. Aliquots of the circulating fluid were withdrawn before irradiation and at 10-sec intervals in the water control and 10-min intervals in the MWF. The samples were diluted with sterile water, plated, and counted after 18-24 hours' incubation. The UV-C radiation output of the lamp was estimated by irradiance measurements using a research radiometer. The concentration of CFU decreased by at least 2 logs (>99% reduction in culturability) in 30 sec in irradiated water. In all three dilutions of MWF, a 2-log decrease was obtained within 60 min. The UV-C output of the lamp was estimated at about 6 W. The disinfection appeared to follow a first order rate law both in MWF and in water. The CFU concentration was stable over time in unirradiated controls. These results demonstrate that UV disinfection is feasible in MWF opaque to both visible and UV wavelengths of light.

  4. Chemometric classification techniques as a tool for solving problems in analytical chemistry.

    Science.gov (United States)

    Bevilacqua, Marta; Nescatelli, Riccardo; Bucci, Remo; Magrì, Andrea D; Magrì, Antonio L; Marini, Federico

    2014-01-01

    Supervised pattern recognition (classification) techniques, i.e., the family of chemometric methods whose aim is the prediction of a qualitative response on a set of samples, represent a very important assortment of tools for solving problems in several areas of applied analytical chemistry. This paper describes the theory behind the chemometric classification techniques most frequently used in analytical chemistry together with some examples of their application to real-world problems.

  5. Developing material for promoting problem-solving ability through bar modeling technique

    Science.gov (United States)

    Widyasari, N.; Rosiyanti, H.

    2018-01-01

    This study aimed at developing material for enhancing problem-solving ability through bar modeling technique with thematic learning. Polya’s steps of problem-solving were chosen as the basis of the study. The methods of the study were research and development. The subject of this study were five teen students of the fifth grade of Lab-school FIP UMJ elementary school. Expert review and student’ response analysis were used to collect the data. Furthermore, the data were analyzed using qualitative descriptive and quantitative. The findings showed that material in theme “Selalu Berhemat Energi” was categorized as valid and practical. The validity was measured by using the aspect of language, contents, and graphics. Based on the expert comments, the materials were easy to implement in the teaching-learning process. In addition, the result of students’ response showed that material was both interesting and easy to understand. Thus, students gained more understanding in learning problem-solving.

  6. A Note on Using Partitioning Techniques for Solving Unconstrained Optimization Problems on Parallel Systems

    Directory of Open Access Journals (Sweden)

    Mehiddin Al-Baali

    2015-12-01

    Full Text Available We deal with the design of parallel algorithms by using variable partitioning techniques to solve nonlinear optimization problems. We propose an iterative solution method that is very efficient for separable functions, our scope being to discuss its performance for general functions. Experimental results on an illustrative example have suggested some useful modifications that, even though they improve the efficiency of our parallel method, leave some questions open for further investigation.

  7. An Accurate Approximate-Analytical Technique for Solving Time-Fractional Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    M. Bishehniasar

    2017-01-01

    Full Text Available The demand of many scientific areas for the usage of fractional partial differential equations (FPDEs to explain their real-world systems has been broadly identified. The solutions may portray dynamical behaviors of various particles such as chemicals and cells. The desire of obtaining approximate solutions to treat these equations aims to overcome the mathematical complexity of modeling the relevant phenomena in nature. This research proposes a promising approximate-analytical scheme that is an accurate technique for solving a variety of noninteger partial differential equations (PDEs. The proposed strategy is based on approximating the derivative of fractional-order and reducing the problem to the corresponding partial differential equation (PDE. Afterwards, the approximating PDE is solved by using a separation-variables technique. The method can be simply applied to nonhomogeneous problems and is proficient to diminish the span of computational cost as well as achieving an approximate-analytical solution that is in excellent concurrence with the exact solution of the original problem. In addition and to demonstrate the efficiency of the method, it compares with two finite difference methods including a nonstandard finite difference (NSFD method and standard finite difference (SFD technique, which are popular in the literature for solving engineering problems.

  8. System of performance indicators for SMEs, metalworking sector

    Directory of Open Access Journals (Sweden)

    Cristina Viteri Sánchez

    2014-03-01

    Full Text Available (Received: 2013/03/05 - Accepted: 2013/03/25This paper focused on the design and proposal of management indicators for small and medium metalworking enterprises (SMEs in Quito. Metalworking number was established for the study. It was met and determined which areas deserve to be constantly monitored, by analyzing the performance of the companies, for this purpose, it was used a SWOT analysis, interviews and meetings with company managers , the results demanded the approach of a generic strategy, which included the formulation of the mission , vision and corporate values. Objectives and goals were established, they were classified according to the four perspectives of the Balanced Scorecard. Then it was possible to identify indicators to measure the proper functioning of the strategy proposed. 10 indicators of management were developed, according to the analysis of the reality of metalworking enterprises. So it was determined 3 financial indicators, 2 indicators focused on customers, 3 indicators for monitor internal business processes and 2 addressed the prospect of learning and growth. The use of these indicators is the key of performance and process control in each metalworking company.

  9. Framework for regional environmental management. [Problem-solving techniques; public relations

    Energy Technology Data Exchange (ETDEWEB)

    Sievering, H.; Sinopoli, J.

    1976-04-01

    A framework for environmental decision-making is described in which both qualitative and quantitative aspects of regional problems can be integrated into a problem-solving context. The techniques employed in this framework are computer simulation, games, and vote-trading. The paper concludes that through this framework: (a) environmental analysts can assess public value structure goal sets which can be used in the development of regional simulations, and (b) in turn, the quantitative aspects of the problems will be more easily communicated to the affected public. A brief description of the application of the framework is also presented.

  10. Solving Reshelving Backlogs in a University Library: A Case Study Using an Interactive Problem-Solving Technique with a TQM Application.

    Science.gov (United States)

    Sheather, Graeme; Nolan, Tony

    1995-01-01

    Describes the application of the General Purpose Utility Problem-Solving technique that was developed at the University of Technology, Sydney, to the problem experienced by a satellite university campus library where there were periodic shelving backlogs. Highlights include cluster methods, total quality management applications, and the use of…

  11. An element search ant colony technique for solving virtual machine placement problem

    Science.gov (United States)

    Srija, J.; Rani John, Rose; Kanaga, Grace Mary, Dr.

    2017-09-01

    The data centres in the cloud environment play a key role in providing infrastructure for ubiquitous computing, pervasive computing, mobile computing etc. This computing technique tries to utilize the available resources in order to provide services. Hence maintaining the resource utilization without wastage of power consumption has become a challenging task for the researchers. In this paper we propose the direct guidance ant colony system for effective mapping of virtual machines to the physical machine with maximal resource utilization and minimal power consumption. The proposed algorithm has been compared with the existing ant colony approach which is involved in solving virtual machine placement problem and thus the proposed algorithm proves to provide better result than the existing technique.

  12. NUMERICAL TECHNIQUES TO SOLVE CONDENSATIONAL AND DISSOLUTIONAL GROWTH EQUATIONS WHEN GROWTH IS COUPLED TO REVERSIBLE REACTIONS (R823186)

    Science.gov (United States)

    Noniterative, unconditionally stable numerical techniques for solving condensational anddissolutional growth equations are given. Growth solutions are compared to Gear-code solutions forthree cases when growth is coupled to reversible equilibrium chemistry. In all cases, ...

  13. Using reflection techniques for flexible problem solving (with examples from diagnosis)

    NARCIS (Netherlands)

    Teije, A. ten; Harmelen, van F.A.H.

    1996-01-01

    Flexible problem solving consists of the dynamic selection and configuration of problem solving methods for a particular problem type, depending on the particular problem and the goal of problem solving. In this paper, we propose an architecture that supports such flexible problem solving

  14. Radioisotope techniques for problem solving in the offshore oil and gas industry

    International Nuclear Information System (INIS)

    Charlton, J.S.; Hurst, J.A.

    1994-01-01

    Radioisotope technology has been used for almost half a century by the oil and gas industry to solve problems and to help optimize process operations. The use of radioactive isotopes to investigate the effectiveness of well stimulation procedures and to measure the sweep-out patterns of oil and gas in secondary recovery process is well known. The applications of radioisotopes to study features of plant and process operation has been less widely reported though the economic benefits deriving from such applications are very great. Nevertheless, there has been continuous development in the range of application and in the design of equipment to facilitate the use of the technology at remote environments such as an oil or gas platform. Some indication of the current usage of radioisotope techniques may be obtained from examination of Table I, which lists projects carried out in the UK's North Sea fields by ICI Tracerco, which is the world's largest radioisotope applications service group

  15. Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques

    International Nuclear Information System (INIS)

    Terzano, Roberto; Santoro, Anna; Spagnuolo, Matteo; Vekemans, Bart; Medici, Luca; Janssens, Koen; Goettlicher, Joerg; Denecke, Melissa A.; Mangold, Stefan; Ruggiero, Pacifico

    2010-01-01

    Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg -1 . Hg chemical forms were identified and quantified by sequential extractions and bulk- and micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as μ-XRF, μ-XRD and μ-XANES were necessary to solve bulk Hg speciation, in both soil fractions 3 S 2 Cl 2 ), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 μm. No interaction among Hg-species and soil components was observed. All the observed Hg-species originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution. - Direct mercury (Hg) speciation in chlor-alkali plant contaminated soils enabled the identification of potentially dangerous Hg-S/Cl amorphous species.

  16. SOLVING THE STUDENTS’ SPEAKING PROBLEM IN DELIVERING ENGLISH PRESENTATION THROUGH 3-P TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Nadif Ulfia

    2017-01-01

    Full Text Available Abstract: Solving the Students’ Speaking Problem in Delivering English Presentation Through 3-P Technique. The aims of this study were to (1 identify whether and to what extent 3-P Technique can improve the students’ speaking competence in delivering presentation;(2 describe the teaching and learning when 3-P technique is implemented in English class. This research was conducted at the eleventh grades of MAN 1 Bojonegoro. The subjects of the research were the teacher and the students in the academic year 2016/2017. This study applied 3 cycle action research. In collecting the data, the researcher used observations through field notes, video recording, questionnaire and interview. To analyze the quantitative data, the researcher applied descriptive statistics. Besides, to analyze qualitative data, the researcher applied constant comparative method as suggested by Garner. The findings shows that: (1 3-P Technique can improve students’ speaking competence in delivering presentation in terms of students achievement, fluency, pronunciation, ability to express their opinions, arguments, and ideas using appropriate vocabulary and grammatical form, using appropriate body language, voice control, gesture, and eye contact; and (2 3-P technique can improve classroom situation in terms of increasing students’ motivation and participation, creating live teaching atmosphere, and increasing teacher motivation. Key words: Speaking, 3 P technique, Action research Abstrak: Memecahkan Masalah Keterampilan Berbicara Siswa dalam Menyampaikan Presentasi Berbahasa Inggris Melalui Teknik 3-P. Tujuan dari penelitian ini adalah untuk (1 mengidentifikasi dan mengetahui sejauh mana teknik 3-P dapat meningkatkan kemampuan berbicara para siswa dalam menyampaikan sebuah presentasi; (2 mendeskripsikan kegiatan pembelajaran dalam penerapan teknik 3-P dalam pembelajaran Bahasa Inggris. Penelitian ini dilakukan pada kelas sebelas MAN 1 Bojonegoro. Subyek  penelitian ini

  17. Vaporization and Conversion of Ethanolamines used in Metalworking Operations.

    Science.gov (United States)

    Kim, Shin-Bum; Yoon, Chung-Sik; Park, Donguk

    2010-12-01

    This study examined how ethanolamines (EAs) with the same functional alcohol group (HOCH(2)CH(2)), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking. Two types of experimental apparatus were manufactured to achieve these objectives. Vaporization tests using a water bath showed that the vaporization rate increased markedly from 0.19 mg/m(2)·min at 23.5℃ to 8.04 mg/m(2)·min at 60℃. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was 0.45 mg/m(3) in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type. MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

  18. PROBLEM SOLVING TECHNIQUES AS A PART OF IMPLEMENTATION OF SIX SIGMA METHODOLOGY IN TIRE PRODUCTION. CASE STUDY

    Directory of Open Access Journals (Sweden)

    Maciej WOJTASZAK

    2015-07-01

    Full Text Available Problem solving methods – are an indispensable part of the management and improvement of production. At the turn of decades, with the development of industry, specific techniques have been implemented and refined by the leaders in this field, such as Toyota, GE and Motorola. The foundation of problem solving is to find real root cause of the problem as soon as possible, its understanding and implementation of appropriate solutions that will ensure that the problem does not occur again. This paper provides an overview of methods and techniques to solve problems in the manufactur-ing plant Trelleborg Wheel Systems Sri Lanka, producing pneumatic tires for light agricultural machinery. These tech-niques are implemented as part of the Lean Six Sigma program.

  19. Predicting Academic Success of Junior Secondary School Students in Mathematics through Cognitive Style and Problem Solving Technique

    Science.gov (United States)

    Badru, Ademola K.

    2015-01-01

    This study examined the prediction of academic success of Junior secondary school mathematics students using their cognitive style and problem solving technique. A descriptive survey of correlation type was adopted for this study. A purposive sampling procedure was used to select five Public Junior secondary schools in Ijebu-Ode local government…

  20. A novel technique to solve nonlinear higher-index Hessenberg differential-algebraic equations by Adomian decomposition method.

    Science.gov (United States)

    Benhammouda, Brahim

    2016-01-01

    Since 1980, the Adomian decomposition method (ADM) has been extensively used as a simple powerful tool that applies directly to solve different kinds of nonlinear equations including functional, differential, integro-differential and algebraic equations. However, for differential-algebraic equations (DAEs) the ADM is applied only in four earlier works. There, the DAEs are first pre-processed by some transformations like index reductions before applying the ADM. The drawback of such transformations is that they can involve complex algorithms, can be computationally expensive and may lead to non-physical solutions. The purpose of this paper is to propose a novel technique that applies the ADM directly to solve a class of nonlinear higher-index Hessenberg DAEs systems efficiently. The main advantage of this technique is that; firstly it avoids complex transformations like index reductions and leads to a simple general algorithm. Secondly, it reduces the computational work by solving only linear algebraic systems with a constant coefficient matrix at each iteration, except for the first iteration where the algebraic system is nonlinear (if the DAE is nonlinear with respect to the algebraic variable). To demonstrate the effectiveness of the proposed technique, we apply it to a nonlinear index-three Hessenberg DAEs system with nonlinear algebraic constraints. This technique is straightforward and can be programmed in Maple or Mathematica to simulate real application problems.

  1. Using Interactive Problem-Solving Techniques to Enhance Control Systems Education for Non English-Speakers

    Science.gov (United States)

    Lamont, L. A.; Chaar, L.; Toms, C.

    2010-01-01

    Interactive learning is beneficial to students in that it allows the continual development and testing of many skills. An interactive approach enables students to improve their technical capabilities, as well as developing both verbal and written communicative ability. Problem solving and communication skills are vital for engineering students; in…

  2. The effects of using diagramming as a representational technique on high school students' achievement in solving math word problems

    Science.gov (United States)

    Banerjee, Banmali

    Methods and procedures for successfully solving math word problems have been, and continue to be a mystery to many U.S. high school students. Previous studies suggest that the contextual and mathematical understanding of a word problem, along with the development of schemas and their related external representations, positively contribute to students' accomplishments when solving word problems. Some studies have examined the effects of diagramming on students' abilities to solve word problems that only involved basic arithmetic operations. Other studies have investigated how instructional models that used technology influenced students' problem solving achievements. Still other studies have used schema-based instruction involving students with learning disabilities. No study has evaluated regular high school students' achievements in solving standard math word problems using a diagramming technique without technological aid. This study evaluated students' achievement in solving math word problems using a diagramming technique. Using a quasi-experimental experimental pretest-posttest research design, quantitative data were collected from 172 grade 11 Hispanic English language learners (ELLS) and African American learners whose first language is English (EFLLs) in 18 classes at an inner city high school in Northern New Jersey. There were 88 control and 84 experimental students. The pretest and posttest of each participating student and samples of the experimental students' class assignments provided the qualitative data for the study. The data from this study exhibited that the diagramming method of solving math word problems significantly improved student achievement in the experimental group (pbenefited from instruction that placed emphasis on the mathematical vocabulary and symbols used in word problems and that both ELLs and EFLLs improved their problem solving success through careful attention to the creation and labeling of diagrams to represent the mathematics

  3. Reflective discourse techniques: From in-class discussions to out-of-classroom problem solving

    Science.gov (United States)

    Wampler, Wendi; Demaree, Dedra; Gilbert, Dennis

    2013-01-01

    Instructors often give prompts that encourage students to articulate their beliefs and conceptions, as well as encourage students to understand the thoughts of their peers. This reflective discourse is used in a calculus-based introductory physics class at Lane Community College, where the instructor explicitly has discourse goals integrated into his course structure. We investigate whether students utilize this discourse when solving problems outside of the classroom context. We interviewed groups of students after the end of spring term, 2012. The students were asked to solve open-ended problems, with analysis focused on whether students applied this reflective discourse. Students were asked a series of follow-up questions to reflect upon their experiences in the course.

  4. An analytical method with Padé technique for solving of variational problems

    Science.gov (United States)

    Jaffarian, H.; Sayevand, K.; Kumar, Sunil

    2017-12-01

    In this paper, the homotopy analysis method (HAM) is employed to solve a class of variational problems (VPs). By using the so-called ħ-curves, we determine the convergence parameter ħ, which plays key role to control convergence of solution series. Also we use Pade' approximant to improve accuracy of the method. Two test example are given to clarify the applicability and efficiency of the proposed method.

  5. Analysis of the efficiency of the linearization techniques for solving multi-objective linear fractional programming problems by goal programming

    Directory of Open Access Journals (Sweden)

    Tunjo Perić

    2017-01-01

    Full Text Available This paper presents and analyzes the applicability of three linearization techniques used for solving multi-objective linear fractional programming problems using the goal programming method. The three linearization techniques are: (1 Taylor’s polynomial linearization approximation, (2 the method of variable change, and (3 a modification of the method of variable change proposed in [20]. All three linearization techniques are presented and analyzed in two variants: (a using the optimal value of the objective functions as the decision makers’ aspirations, and (b the decision makers’ aspirations are given by the decision makers. As the criteria for the analysis we use the efficiency of the obtained solutions and the difficulties the analyst comes upon in preparing the linearization models. To analyze the applicability of the linearization techniques incorporated in the linear goal programming method we use an example of a financial structure optimization problem.

  6. Potential pathogenic bacteria in metalworking fluids and aerosols from a machining facility.

    Science.gov (United States)

    Perkins, Sarah D; Angenent, Largus T

    2010-12-01

    The metalworking and machining industry utilizes recirculating metalworking fluids for integral aspects of the fabrication process. Despite the use of biocides, these fluids sustain substantial biological growth. Subsequently, the high-shear forces incurred during metalworking processing aerosolize bacterial cells and may cause dermatologic and respiratory effects in exposed workers. We quantified and identified the bacterial load for metalworking fluid and aerosol samples of a machining facility in the US Midwest during two seasons. To investigate the presence of potentially pathogenic bacteria in fluid and air, we performed 16S rRNA gene surveys. The concentration of total bacterial cells (including culturable and nonculturable cells) was relatively constant throughout the study, averaging 5.1 × 10⁸ cells mL⁻¹ in the fluids and 4.8 × 10⁵ cells m⁻³ in the aerosols. We observed bacteria of potential epidemiologic significance from several different bacterial phyla in both fluids and aerosols. Most notably, Alcaligenes faecalis was identified through both direct sequencing and culturing in every sample collected. Elucidating the bacterial community with gene surveys showed that metalworking fluids were the source of the aerosolized bacteria in this facility. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  7. Solving Multi-Pollutant Emission Dispatch Problem Using Computational Intelligence Technique

    Directory of Open Access Journals (Sweden)

    Nur Azzammudin Rahmat

    2016-06-01

    Full Text Available Economic dispatch is a crucial process conducted by the utilities to correctly determine the satisfying amount of power to be generated and distributed to the consumers. During the process, the utilities also consider pollutant emission as the consequences of fossil-fuel consumption. Fossil-fuel includes petroleum, coal, and natural gas; each has its unique chemical composition of pollutants i.e. sulphur oxides (SOX, nitrogen oxides (NOX and carbon oxides (COX. This paper presents multi-pollutant emission dispatch problem using computational intelligence technique. In this study, a novel emission dispatch technique is formulated to determine the amount of the pollutant level. It utilizes a pre-developed optimization technique termed as differential evolution immunized ant colony optimization (DEIANT for the emission dispatch problem. The optimization results indicated high level of COX level, regardless of any type of fossil fuel consumed.

  8. Using interactive problem-solving techniques to enhance control systems education for non English-speakers

    Science.gov (United States)

    Lamont, L. A.; Chaar, L.; Toms, C.

    2010-03-01

    Interactive learning is beneficial to students in that it allows the continual development and testing of many skills. An interactive approach enables students to improve their technical capabilities, as well as developing both verbal and written communicative ability. Problem solving and communication skills are vital for engineering students; in the workplace they will be required to communicate with people of varying technical abilities and from different linguistic and engineering backgrounds. In this paper, a case study is presented that discusses how the traditional method of teaching control systems can be improved. 'Control systems' is a complex engineering topic requiring students to process an extended amount of mathematical formulae. MATLAB software, which enables students to interactively compare a range of possible combinations and analyse the optimal solution, is used to this end. It was found that students became more enthusiastic and interested when given ownership of their learning objectives. As well as improving the students' technical knowledge, other important engineering skills are also improved by introducing an interactive method of teaching.

  9. Applications of computational intelligence techniques for solving the revived optimal power flow problem

    Energy Technology Data Exchange (ETDEWEB)

    AlRashidi, M.R. [Electrical Engineering Department, College of Technological Studies, Shuwaikh (Kuwait); El-Hawary, M.E. [Department of Electrical and Computer Engineering, Dalhousie University, Halifax, NS B3J 2X4 (Canada)

    2009-04-15

    Computational intelligence tools are attracting added attention in different research areas and research in power systems is not different. This paper provides an overview of major computational issues with regard to the optimal power flow (OPF). Then, it offers a brief summary of major computational intelligence tools. A detailed coverage of most OPF related research work that make use of modern computational intelligence techniques is presented next. (author)

  10. Video demonstrations seed alternative problem-solving techniques in wild common marmosets

    OpenAIRE

    Gunhold, Tina; Whiten, Andrew; Bugnyar, Thomas

    2014-01-01

    Studies of social learning and tradition formation under field conditions have recently gained momentum, but suffer from the limited control of socio-ecological factors thought to be responsible for transmission patterns. The use of artificial visual stimuli is a potentially powerful tool to overcome some of these problems. Here, in a field experiment, we used video images of unfamiliar conspecifics performing virtual demonstrations of foraging techniques. We tested 12 family groups of wild c...

  11. Comparison of AI techniques to solve combined economic emission dispatch problem with line flow constraints

    International Nuclear Information System (INIS)

    Jacob Raglend, I.; Veeravalli, Sowjanya; Sailaja, Kasanur; Sudheera, B.; Kothari, D.P.

    2010-01-01

    A comparative study has been made on the solutions obtained using combined economic emission dispatch (CEED) problem considering line flow constraints using different intelligent techniques for the regulated power system to ensure a practical, economical and secure generation schedule. The objective of the paper is to minimize the total production cost of the power generation. Economic load dispatch (ELD) and economic emission dispatch (EED) have been applied to obtain optimal fuel cost of generating units. Combined economic emission dispatch (CEED) is obtained by considering both the economic and emission objectives. This bi-objective CEED problem is converted into single objective function using price penalty factor approach. In this paper, intelligent techniques such as genetic algorithm (GA), evolutionary programming (EP), particle swarm optimization (PSO), differential evolution (DE) are applied to obtain CEED solutions for the IEEE 30-bus system and 15-unit system. This proposed algorithm introduces an efficient CEED approach that obtains the minimum operating cost satisfying unit, emission and network constraints. The proposed algorithm has been tested on two sample systems viz the IEEE 30-bus system and a 15-unit system. The results obtained by the various artificial intelligent techniques are compared with respect to the solution time, total production cost and convergence criteria. The solutions obtained are quite encouraging and useful in the economic emission environment. The algorithm and simulation are carried out using Matlab software. (author)

  12. Efficient combination of acceleration techniques applied to high frequency methods for solving radiation and scattering problems

    Science.gov (United States)

    Lozano, Lorena; Algar, Ma Jesús; García, Eliseo; González, Iván; Cátedra, Felipe

    2017-12-01

    An improved ray-tracing method applied to high-frequency techniques such as the Uniform Theory of Diffraction (UTD) is presented. The main goal is to increase the speed of the analysis of complex structures while considering a vast number of observation directions and taking into account multiple bounces. The method is based on a combination of the Angular Z-Buffer (AZB), the Space Volumetric Partitioning (SVP) algorithm and the A∗ heuristic search method to treat multiple bounces. In addition, a Master Point strategy was developed to analyze efficiently a large number of Near-Field points or Far-Field directions. This technique can be applied to electromagnetic radiation problems, scattering analysis, propagation at urban or indoor environments and to the mutual coupling between antennas. Due to its efficiency, its application is suitable to study large antennas radiation patterns and even its interactions with complex environments, including satellites, ships, aircrafts, cities or another complex electrically large bodies. The new technique appears to be extremely efficient at these applications even when considering multiple bounces.

  13. Rectal cancer and exposure to metalworking fluids in the automobile manufacturing industry.

    Science.gov (United States)

    Malloy, Elizabeth J; Miller, Katie L; Eisen, Ellen A

    2007-04-01

    Rectal cancer has been previously associated with exposure to metalworking fluids in a cohort mortality study of autoworkers. To better specify the exposure-response relationship with straight metalworking fluids (mineral oils) by applying non-parametric regression methods that avoid linearity constraints and arbitrary exposure cut points and by lagging exposure to account for cancer latency, in a nested case-control analysis. In addition to the classical Poisson regression with categorical exposure, survival models with penalised splines were used to estimate the exposure-response relationship between cumulative exposure to straight metalworking fluid and mortality from rectal cancer. Exposures to water-based metalworking fluids were treated as potential confounders, and all exposures were lagged by 5, 10, 15 and 20 years to account for cancer latency. The influence of the highest exposures was dealt with by a log transformation and outlier removal. The sensitivity of the penalised splines to alternative criteria for model selection and to the placement of knots was also examined. The hazard ratio for mortality from rectal cancer increased essentially linearly with cumulative exposure to straight metalworking fluid (with narrow confidence bands) up to a maximum of 2.2 at the 99th centile of exposure and then decreased (with wide confidence bands). Lagging exposure up to 15 years increased the initial steepness of the curve and raised the maximum hazard ratio to 3.2. Non-parametric smoothing of lagged exposures has shown stronger evidence for a causal association between straight metalworking fluid and rectal cancer than was previously described using standard analytical methods. This analysis suggests an exposure-response trend that is close to linear and statistically significant over most of the exposure range and that increases further with lagged exposures. Smoothing should be regularly applied to environmental studies with quantitative exposure estimates to

  14. Application of Modern Experimental Technique to Solve Morphological Complexity in Plants Taxonomy

    Directory of Open Access Journals (Sweden)

    SURANTO

    2000-07-01

    Full Text Available Modern taxonomy has two approaches, i.e. classical and experimental taxonomy. Classical taxonomy uses morphological characters, while experimental taxonomy uses broader methods including chemistry, physics and mathematics, in the form of laboratory data that are revealed together with the progress of optical technique (microscope, chemistry methods (chromatography, electrophoresis, etc. Modern taxonomy tends to use series of interrelated data. More data used would result in more validity and give better clarification of taxonomic status. A lot of modern taxonomic data such as palynology, cytotaxonomy (cytology, chemical constituent (chemotaxonomy, isozyme and DNA sequencing were used recently.

  15. A method for solving equally spread symmetric fuzzy assignment problems using branch and bound technique

    Science.gov (United States)

    Muralidaran, C.; Venkateswarlu, B.

    2017-11-01

    The fuzzy assignment model depicts a special case of fuzzy linear programming problem (F.L.P.P) in which the objective is to assign the number of origins to the same number of destinations at minimum total cost. The fuzzy assignment should be framed on one-to-one basis. In this research article it is developed a method using the Branch and Bound Technique has been developed for symmetric fuzzy assignment (equally spread) of jobs. Also in this method fuzzy optimal solution has been obtained without converting the symmetric fuzzy assignment problem (equally spread) as a crisp.

  16. Video demonstrations seed alternative problem-solving techniques in wild common marmosets.

    Science.gov (United States)

    Gunhold, Tina; Whiten, Andrew; Bugnyar, Thomas

    2014-09-01

    Studies of social learning and tradition formation under field conditions have recently gained momentum, but suffer from the limited control of socio-ecological factors thought to be responsible for transmission patterns. The use of artificial visual stimuli is a potentially powerful tool to overcome some of these problems. Here, in a field experiment, we used video images of unfamiliar conspecifics performing virtual demonstrations of foraging techniques. We tested 12 family groups of wild common marmosets. Six groups received video demonstrations (footage of conspecifics either pulling a drawer open or pushing a lid upwards, in an 'artificial fruit'); the other six groups served as controls (exposed to a static image of a conspecific next to the fruit). Subjects in video groups were more manipulative and successful in opening the fruit than controls; they were also more likely to use the technique they had witnessed and thus could serve as live models for other family members. To our knowledge, this is the first study that used video demonstrations in the wild and demonstrated the potent force of social learning, even from unfamiliar conspecifics, under field conditions. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. Application and verification of cold air velocity technique for solving tube ash erosion problem in PC boilers

    International Nuclear Information System (INIS)

    Yoo, Kisoo; Jeong, Kwon Seok

    2012-01-01

    Fly ash erosion is a leading cause of boiler tube failure in PC boilers. Therefore, shields or baffle plates are installed in specific areas to mitigate fly ash erosion and prevent boiler tube failure. However, the tube failure problems caused by fly ash erosion cannot be eliminated with this solution alone, because each PC boiler has a different flue gas flow pattern and erosion can become severe in unexpected zones. This problem is caused by an asymmetric internal flow velocity and local growth of the flue gas velocity. For these reasons, clearly defining the flow pattern in PC boilers is important for solving the problem of tube failure caused by fly ash erosion. For this purpose, the cold air velocity technique (CAVT) can be applied to the fly ash erosion problem. In this study, CAVT was carried out on the Hadong 2 PC boiler and the feasibility of application of CAVT to conventional PC boilers was validated

  18. Automatic approach to solve the morphological galaxy classification problem using the sparse representation technique and dictionary learning

    Science.gov (United States)

    Diaz-Hernandez, R.; Ortiz-Esquivel, A.; Peregrina-Barreto, H.; Altamirano-Robles, L.; Gonzalez-Bernal, J.

    2016-06-01

    The observation of celestial objects in the sky is a practice that helps astronomers to understand the way in which the Universe is structured. However, due to the large number of observed objects with modern telescopes, the analysis of these by hand is a difficult task. An important part in galaxy research is the morphological structure classification based on the Hubble sequence. In this research, we present an approach to solve the morphological galaxy classification problem in an automatic way by using the Sparse Representation technique and dictionary learning with K-SVD. For the tests in this work, we use a database of galaxies extracted from the Principal Galaxy Catalog (PGC) and the APM Equatorial Catalogue of Galaxies obtaining a total of 2403 useful galaxies. In order to represent each galaxy frame, we propose to calculate a set of 20 features such as Hu's invariant moments, galaxy nucleus eccentricity, gabor galaxy ratio and some other features commonly used in galaxy classification. A stage of feature relevance analysis was performed using Relief-f in order to determine which are the best parameters for the classification tests using 2, 3, 4, 5, 6 and 7 galaxy classes making signal vectors of different length values with the most important features. For the classification task, we use a 20-random cross-validation technique to evaluate classification accuracy with all signal sets achieving a score of 82.27 % for 2 galaxy classes and up to 44.27 % for 7 galaxy classes.

  19. The Study Of Metalworking Fluids Biodegradability By Indirect Measurement Of Bacterial Inoculum Respiration

    Directory of Open Access Journals (Sweden)

    Gerulová Kristína

    2015-06-01

    Full Text Available An apparatus for measuring biodegradability of metalworking fluids (MWFs was constructed according to (1, based on the Zahn-Wellens test which enables a continuous determination of CO2 production by the change in conductivity of absorption solution. Results obtained from the testing of 8 different MWFs by this modified method were compared to those obtained in standardized OECD 302 B. The comparison showed better description of bacterial inoculum activity in tested solution; lag phase was easy to indicate. Tested emulsion achieved the level of primary degradability 39.7 – 40.8 %, and semi-synthetics 19.1 – 43.5%. The samples of synthetics where the degradation level reached 43.9 - 58.6 % were identified as the most degradable metalworking fluids.

  20. Evaluation of Anti-Wear Properties of Metalworking Fluids Enhanced with Halloysite Nanotubes

    Directory of Open Access Journals (Sweden)

    Laura Peña-Parás

    2017-10-01

    Full Text Available The study of nanoparticles as additives for metalworking fluids (MWFs with applications in the metal removal processes, or machining, has received increasing attention due to the possible enhancements on tribological properties. In this study, low-cost and environmentally friendly nanoparticle additives of halloysite clay nanotubes (HNTs were dispersed in metalworking fluids utilized for milling processes. Concentrations of 0.01, 0.05, 0.10 wt. % were incorporated into a mineral oil (MO and a semi-synthetic fluid (SF by ultrasonication. The anti-wear properties of metalworking nanofluids were characterized with a T-05 block-on-ring tribotester at a contact pressure of 0.5 GPa. Surface roughness of worn block materials was obtained with an optical 3D surface measurement system. Results showed that at a concentration of 0.10 wt. % HNTs block mass loss was lowered by 24% for the MO + HNTs nanofluids. For the SF + HNTs, a reduction of 63% and 32% in wear mass loss and coefficient of friction (COF, respectively, were found at the same concentration. The tribological enhancing mechanism for the applied contact pressure was proposed to be due to a reduction of the area of contact and nanoparticle sliding between surfaces with no HNT deposition, evidenced by energy dispersive spectrometry (EDS. Furthermore, surface roughness studies of worn blocks showed smoother surfaces with lower groove density with the addition of nanoparticle additives. The results of this study demonstrate that HNTs can improve the lubricity of metalworking cutting fluids used for machining processes, enhancing tool life and providing better surface finish of products.

  1. A new efficient analytical method for a system of vibration. Structural analysis using a new technique of partially solving method

    International Nuclear Information System (INIS)

    Gunyasu, Kenzo; Hiramoto, Tsuneyuki; Tanimoto, Mitsumori; Osano, Minetada

    2002-01-01

    We describe a new method for solving large-scale system of linear equations resulting from discretization of ordinary differential equation and partial differential equation directly. This new method effectively reduces the memory capacity requirements and computing time problems for analyses using finite difference method and finite element method. In this paper we have tried to solve one-million linear equations directly for the case that initial displacement and boundary displacement are known about the finite difference scheme of second order inhomogeneous differential equation for vibration of a 10 story structure. Excellent results were got. (author)

  2. The Effects of Using Diagramming as a Representational Technique on High School Students' Achievement in Solving Math Word Problems

    Science.gov (United States)

    Banerjee, Banmali

    2010-01-01

    Methods and procedures for successfully solving math word problems have been, and continue to be a mystery to many U.S. high school students. Previous studies suggest that the contextual and mathematical understanding of a word problem, along with the development of schemas and their related external representations, positively contribute to…

  3. Determination of the sources of copper and lead used for British bronze age metalwork by lead isotope analysis

    International Nuclear Information System (INIS)

    Rohl, B.M.

    1997-01-01

    This presentation highlights the results of the work carried out by the author during her doctoral research regarding the use of lead isotope analysis to investigate the source of copper and lead for the metalwork during the British Bronze Age. Over 450 new lead isotope analyses of ore samples from England and Wales were compared with published data from Britain, Ireland, France and Germany. In addition, more than 400 pieces of metalwork, representing all phases of the British Bronze Age, were analysed. Many of these pieces of metalwork had previously been analysed for their chemical and impurity content, and supplementary chemical analyses were made to investigate a possible chemical/lead isotope relationship. The ores show overlapping isotopic distributions, while the artefacts show intriguing shifts in the lead isotope signature, with coherent pattern recognizable throughout the Bronze Age phases and regionally

  4. Proposal for the award of an industrial support contract for minor metalwork, metal fittings, cladding and roofing at CERN

    CERN Document Server

    2006-01-01

    This document concerns the award of a contract for minor metalwork, metal fittings, cladding and roofing at CERN. The Finance Committee is invited to agree to the negotiation of a contract with the firm INIZIATIVE INDUSTRIALI SRL (IT), the lowest bidder, for the provision of minor metalwork, metal fittings, cladding and roofing at CERN for three years for a total amount not exceeding 1 467 895 euros (2 258 301 Swiss francs), not subject to revision for two years. The contract will include options for two one-year extensions beyond the initial three-year period.

  5. The Study Into Potential Enhacement Of Metalworking Fluids Biodegradability By The Application Of O3/UV

    Directory of Open Access Journals (Sweden)

    Gerulová Kristína

    2015-06-01

    Full Text Available The increase in mineralization and biodegradability of MWFs by ozone/ultraviolet in comparison with ozone were investigated. Studied were two similar synthetic fluids pre-treated by the combination of the O3/UV advanced oxidative method. Expectations that the pre-treatment could enhance biodegradability of the metalworking fluid were not confirmed. The combined oxidation process at the defined conditions resulted in 1-35 % decrease of the achieved primary degradation level. Samples were prepared from real concentrates and diluted to approximately 350 mg/L of TOC.

  6. Feasibility Study – Using a Solar Evaporator to Reduce the Metalworking Fluid (MWF) Waste Stream

    Energy Technology Data Exchange (ETDEWEB)

    Lazarus, Lloyd

    2008-12-03

    A solar evaporator was designed, built, and operated to reduce the water-based metalworking fluid waste stream. The evaporator was setup in Waste Management’s barrel lot inside one of the confinement areas. The unit processed three batches of waste fluid during the prototype testing. Initial tests removed 13% of the fluid waste stream. Subsequent modifications to the collector improved the rate to almost 20% per week. Evaluation of the risk during operation showed that even a small spill when associated with precipitation, and the unit placement within a confinement area, gave it the potential to contaminate more fluid that what it could save.

  7. The Occupational Exposure Limit for Fluid Aerosol Generated in Metalworking Operations: Limitations and Recommendations

    Directory of Open Access Journals (Sweden)

    Donguk Park

    2012-03-01

    Full Text Available The aim of this review was to assess current knowledge related to the occupational exposure limit (OEL for fluid aerosols including either mineral or chemical oil that are generated in metalworking operations, and to discuss whether their OEL can be appropriately used to prevent several health risks that may vary among metalworking fluid (MWF types. The OEL (time-weighted average; 5 mg/m3, short-term exposure limit ; 15 mg/m3 has been applied to MWF aerosols without consideration of different fluid aerosol-size fractions. The OEL, is also based on the assumption that there are no significant differences in risk among fluid types, which may be contentious. Particularly, the health risks from exposure to water-soluble fluids may not have been sufficiently considered. Although adoption of The National Institute for Occupational Safety and Health's recommended exposure limit for MWF aerosol (0.5 mg/m3 would be an effective step towards minimizing and evaluating the upper respiratory irritation that may be caused by neat or diluted MWF, this would fail to address the hazards (e.g., asthma and hypersensitivity pneumonitis caused by microbial contaminants generated only by the use of water-soluble fluids. The absence of an OEL for the water-soluble fluids used in approximately 80-90 % of all applicants may result in limitations of the protection from health risks caused by exposure to those fluids.

  8. Community-acquired Pseudomonas aeruginosa-pneumonia in a previously healthy man occupationally exposed to metalworking fluids

    Directory of Open Access Journals (Sweden)

    Fernando Peixoto Ferraz de Campos

    2014-09-01

    Full Text Available Although the Pseudomonas aeruginosa infection is well known and frequently found in hospitals and nursing care facilities, many cases are also reported outside these boundaries. In general, this pathogen infects debilitated patients either by comorbidities or by any form of immunodeficiency. In cases of respiratory infection, tobacco abuse seems to play an important role as a risk factor. In previously healthy patients, community-acquired pneumonia (CAP with P. aeruginosa as the etiological agent is extremely rare, and unlike the cases involving immunocompromised or hospitalized patients, the outcome is severe, and is fatal in up to 61.1% of cases. Aerosolized contaminated water or solutions are closely linked to the development of respiratory tract infection. In this setting, metalworking fluids used in factories may be implicated in CAP involving previously healthy people. The authors report the case of a middle-aged man who worked in a metalworking factory and presented a right upper lobar pneumonia with a rapid fatal outcome. P. aeruginosa was cultured from blood and tracheal aspirates. The autopsy findings confirmed a hemorrhagic necrotizing pneumonia with bacteria-invading vasculitis and thrombosis. A culture of the metalworking fluid of the factory was also positive for P. aeruginosa. The pulsed-field gel electrophoresis showed that both strains (blood culture and metalworking fluid were genetically indistinguishable. The authors highlight the occupational risk for the development of this P. aeruginosa-infection in healthy people.

  9. Pseudo-point transport technique: a new method for solving the Boltzmann transport equation in media with highly fluctuating cross sections

    International Nuclear Information System (INIS)

    Nakhai, B.

    1979-01-01

    A new method for solving radiation transport problems is presented. The heart of the technique is a new cross section processing procedure for the calculation of group-to-point and point-to-group cross sections sets. The method is ideally suited for problems which involve media with highly fluctuating cross sections, where the results of the traditional multigroup calculations are beclouded by the group averaging procedures employed. Extensive computational efforts, which would be required to evaluate double integrals in the multigroup treatment numerically, prohibit iteration to optimize the energy boundaries. On the other hand, use of point-to-point techniques (as in the stochastic technique) is often prohibitively expensive due to the large computer storage requirement. The pseudo-point code is a hybrid of the two aforementioned methods (group-to-group and point-to-point) - hence the name pseudo-point - that reduces the computational efforts of the former and the large core requirements of the latter. The pseudo-point code generates the group-to-point or the point-to-group transfer matrices, and can be coupled with the existing transport codes to calculate pointwise energy-dependent fluxes. This approach yields much more detail than is available from the conventional energy-group treatments. Due to the speed of this code, several iterations could be performed (in affordable computing efforts) to optimize the energy boundaries and the weighting functions. The pseudo-point technique is demonstrated by solving six problems, each depicting a certain aspect of the technique. The results are presented as flux vs energy at various spatial intervals. The sensitivity of the technique to the energy grid and the savings in computational effort are clearly demonstrated

  10. A case-control study of occupational exposure to metalworking fluids and bladder cancer risk among men.

    Science.gov (United States)

    Colt, Joanne S; Friesen, Melissa C; Stewart, Patricia A; Donguk, Park; Johnson, Alison; Schwenn, Molly; Karagas, Margaret R; Armenti, Karla; Waddell, Richard; Verrill, Castine; Ward, Mary H; Freeman, Laura E Beane; Moore, Lee E; Koutros, Stella; Baris, Dalsu; Silverman, Debra T

    2014-10-01

    Metalworking has been associated with an excess risk of bladder cancer in over 20 studies. Metalworking fluids (MWFs) are suspected as the responsible exposure, but epidemiological data are limited. We investigated this association among men in the New England Bladder Cancer Study using state-of-the-art, quantitative exposure assessment methods. Cases (n=895) and population controls (n=1031) provided occupational histories during personal interviews. For selected jobs, exposure-oriented modules were administered to collect information on use of three MWF types: (1) straight (mineral oil, additives), (2) soluble (mineral oil, water, additives) and (3) synthetic (water, organics, additives) or semisynthetic (hybrid of soluble and synthetic). We computed ORs and 95% CIs relating bladder cancer risk to a variety of exposure metrics, adjusting for smoking and other factors. Non-metalworkers who had held jobs with possible exposure to mineral oil were analysed separately. Bladder cancer risk was elevated among men who reported using straight MWFs (OR=1.7, 95% CI 1.1 to 2.8); risk increased monotonically with increasing cumulative exposure (p=0.041). Use of soluble MWFs was associated with a 50% increased risk (95% CI 0.96 to 2.5). ORs were non-significantly elevated for synthetic/semisynthetic MWFs based on a small number of exposed men. Non-metalworkers holding jobs with possible exposure to mineral oil had a 40% increased risk (95% CI 1.1 to 1.8). Exposure to straight MWFs was associated with a significantly increased bladder cancer risk, as was employment in non-metalworking jobs with possible exposure to mineral oil. These findings strengthen prior evidence for mineral oil as a bladder carcinogen. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. Plastic limit analysis with non linear kinematic strain hardening for metalworking processes applications

    International Nuclear Information System (INIS)

    Chaaba, Ali; Aboussaleh, Mohamed; Bousshine, Lahbib; Boudaia, El Hassan

    2011-01-01

    Limit analysis approaches are widely used to deal with metalworking processes analysis; however, they are applied only for perfectly plastic materials and recently for isotropic hardening ones excluding any kind of kinematic hardening. In the present work, using Implicit Standard Materials concept, sequential limit analysis approach and the finite element method, our objective consists in extending the limit analysis application for including linear and non linear kinematic strain hardenings. Because this plastic flow rule is non associative, the Implicit Standard Materials concept is adopted as a framework of non standard plasticity modeling. The sequential limit analysis procedure which considers the plastic behavior with non linear kinematic strain hardening as a succession of perfectly plastic behavior with yielding surfaces updated after each sequence of limit analysis and geometry updating is applied. Standard kinematic finite element method together with a regularization approach is used for performing two large compression cases (cold forging) in plane strain and axisymmetric conditions

  12. Solving geological and historical puzzles with advanced gemologic techniques: The Franco Dávila (1772) precious opal case

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Guinea, J.; Gonzalez-Alcalde, J.; Furio, M.; Jorge, A.; Garrido, F.

    2016-07-01

    The large precious opal weighting 33 grams fitted in a silver jewel and exposed to visitors at the Museo Nacional de Ciencias Naturales (MNCN) is well documented in: (i) its own mounting (1772), (ii) at the 775 document of the Archive of the MNCN and (iii) the 395 specimen described in the of Pedro Franco Dávila catalogue. The X-ray diffractogram (XRD) performed onto the opal block is very similar to other opals of volcanic origin containing varied amounts of cristobalite, tridymite and amorphous silica. The Raman spectrum shows a band peaked at 242, 343 and 416 cm−1 associated with O-Si-O stretching groups; other spectral band peaked at 780 and 819 cm−1 corresponding to vibration of symmetrical O-Si-O rings of 3 and 4 link members, plus other minor bands. The Raman spectrum is also very similar to those observed in Mexican opals of volcanic origin containing an spectral band of stretching nodes ν1 (OH) at 3233, 3393, 3511, 3628 cm−1 related to OH groups with hydrogen bonds of isolated silanol groups. The interferometric confocal dual microscope 3D (MCI3D), which is a nondestructive facility of high resolution and LED technology reveals the geometry of graver tools on the silver jewel and the computed tomography X-ray highlights the opal cutting as a squared princess type and silver chloride infillings of a crack probably caused by a shock on a corner. Under the scanning electron microscope we observed barite, sealed veins of silica rich in Mn and opal with high contents of Al and K which, along with the historical data, the piece can be attributed to the historical site of opals hosted in Slovakia andesite rocks, this data explains the optical light behavior in the cabochon. The silver jewel has large amounts of Hg and AgCl indicating amalgam method. In addition the natural AgS2 phases probably come from Nueva España (year 1772) in full production of silver in such time. The association of new analytical non-destructive techniques combines the

  13. Comparative analysis of export capabilities of the metalworking industry in Zlatibor region and the rest of Serbia

    Directory of Open Access Journals (Sweden)

    Brkić-Spasojević Vesna K.

    2016-01-01

    Full Text Available Exporting is very important activity for companies settled in developing countries, while manufacturing industry is the most important section of the EU economy that drives its growth and propels its technological and innovation development, so it is expected that export in that sector is extremely important activity from national economy point of view. Accordingly, the topic of this survey deals with export possibilities of metalworking industry and compares Zlatibor region export capabilities to export capabilities of the rest of Serbian metalworking companies to EU. There aren't many significant distinctions in export capabilities of Zlatibor region and the rest of Serbia, and they are mainly related to knowledge of regulations. Namely, a significant number of companies is not familiar with new approach directives, as well as with procedures for conformity assessment. Recommendation is more careful choice of suppliers that satisfy necessary requirements, too.

  14. On the generalization of constraint programming and boolean satisfiability solving techniques to schedule a resource-constrained project consisting of multi-mode jobs

    Directory of Open Access Journals (Sweden)

    Alexander Schnell

    Full Text Available In our paper, we analyze new exact approaches for the multi-mode resource-constrained project scheduling (MRCPSP problem with the aim of makespan minimization. For the single-mode RCPSP (SRCPSP recent exact algorithms combine a Branch and Bound algorithm with principles from Constraint Programming (CP and Boolean Satisfiability Solving (SAT. We extend the above principles for the solution of MRCPSP instances. This generalization is on the one hand achieved on the modeling level. We propose three CP-based formulations of the MRCPSP for the G12 CP platform and the optimization framework SCIP which both provide solution techniques combining CP and SAT principles. For one of the latter we implemented a new global constraint for SCIP, which generalizes the domain propagation and explanation generation principles for renewable resources in the context of multi-mode jobs. Our constraint applies the above principles in a more general way than the existing global constraint in SCIP. We compare our approaches with the state-of-the-art exact algorithm from the literature on MRCPSP instances with 20 and 30 jobs. Our computational experiments show that we can outperform the latter approach on these instances. Furthermore, we are the first to close (find the optimal solution and prove its optimality for 628 open instances with 50 and 100 jobs from the literature. In addition, we improve the best known lower bound of 2815 instances and the best known upper bound of 151 instances. Keywords: Multi-mode resource-constrained project scheduling, Constraint programming, SAT solving, SCIP, Lazy clause generation, Exact algorithm

  15. Tribological evaluation of hexagonal boron nitride in modified jatropha oil as sustainable metalworking fluid

    Science.gov (United States)

    Talib, Norfazillah; Rahim, Erween Abd.; Nasir, Ramdziah Md.

    2017-11-01

    The used of metalworking fluids (MWFs) from petroleum-based oil during machining process contributed negative impact to the humans and environment. Therefore, bio-based oil from vegetable oil was recently explored as an alternative solution to petroleum-based oil to implement sustainable manufacturing process. In this study, modified jatropha oil (MJO5) with and without hexagonal boron nitride (hBN) particles were evaluated through friction and wear test and orthogonal cutting performance in comparison with synthetic ester (SE). MJO5 were mixed with hBN particles at various concentrations (i.e. 0.05, 0.1 and 0.5wt.%). Experimental results showed that the addition of 0.05wt.% of hBN particles in MJO5 (MJO5a) provided lowest coefficient of friction (COF) and smallest wear scar diameter (WSD). MJO5a has the best anti-friction ability by reducing the cutting force and cutting temperature which related to the formation of thinner chips and small tool-chip contact length. MJO5a is the best substitute to SE as sustainable MWFs in the machining operation in regards to the environmental and health concern.

  16. Integral methodology simulation support for the improvement of production systems job shop. Metalworking applications in SMES

    Directory of Open Access Journals (Sweden)

    Jaime Alberto Giraldo García

    2010-01-01

    Full Text Available Metalworking companies represent one of the strategic sectors in the regional economy of the Caldas department in Colombia; in fact, this sector is involved in 31% of the department’s industrial establishments and 29% of industrial employment according to DANE (Colombian State Statistical Department statistical data from 2005. The sector also exports to Andean countries. However, preliminary studies conducted with 57% of the entrepreneurs from this sector (excluding micro companies and family businesses have revealed serious structural (technology, processing, installations and infrastructure weaknesses (production planning, quality systems in these organisations’ production systems. It is hoped that this paper will lead to disseminating the results amongst the academic community of implementing a comprehensive methodology for improving the production system of a pilot company from this particular sector. An experimental framework for improving the levels reached by the system regarding such priorities is proposed following universally accepted methodology in discrete simulation studies; it proposes using sequential bifurcation, factorial design and response surface experimentation based on defining and weighting the competing priorities which the company should achieve. The improvements in the pilot company’s production system priorities are presented in terms of an effectiveness index (EI which rose from 1.84 to 2.46 by the end of the study.

  17. Ra and the average effective strain of surface asperities deformed in metal-working processes

    DEFF Research Database (Denmark)

    Bay, Niels; Wanheim, Tarras; Petersen, A. S

    1975-01-01

    Based upon a slip-line analysis of the plastic deformation of surface asperities, a theory is developed determining the Ra-value (c.l.a.) and the average effective strain in the surface layer when deforming asperities in metal-working processes. The ratio between Ra and Ra0, the Ra-value after...... and before deformation, is a function of the nominal normal pressure and the initial slope γ0 of the surface asperities. The last parameter does not influence Ra significantly. The average effective strain View the MathML sourcege in the deformed surface layer is a function of the nominal normal pressure...... and γ0. View the MathML sourcege is highly dependent on γ0, View the MathML sourcege increasing with increasing γ0. It is shown that the Ra-value and the strain are hardly affected by the normal pressure until interacting deformation of the asperities begins, that is until the limit of Amonton's law...

  18. Problem Solving and Learning

    Science.gov (United States)

    Singh, Chandralekha

    2009-07-01

    One finding of cognitive research is that people do not automatically acquire usable knowledge by spending lots of time on task. Because students' knowledge hierarchy is more fragmented, "knowledge chunks" are smaller than those of experts. The limited capacity of short term memory makes the cognitive load high during problem solving tasks, leaving few cognitive resources available for meta-cognition. The abstract nature of the laws of physics and the chain of reasoning required to draw meaningful inferences makes these issues critical. In order to help students, it is crucial to consider the difficulty of a problem from the perspective of students. We are developing and evaluating interactive problem-solving tutorials to help students in the introductory physics courses learn effective problem-solving strategies while solidifying physics concepts. The self-paced tutorials can provide guidance and support for a variety of problem solving techniques, and opportunity for knowledge and skill acquisition.

  19. Digital tomosynthesis as a problem-solving imaging technique to confirm or exclude potential thoracic lesions based on chest X-ray radiography.

    Science.gov (United States)

    Quaia, Emilio; Baratella, Elisa; Poillucci, Gabriele; Kus, Sara; Cioffi, Vincenzo; Cova, Maria Assunta

    2013-05-01

    To assess the capability of digital tomosynthesis (DTS) as a problem-solving imaging technique to confirm or exclude potential thoracic lesions based on chest x-ray radiography (CXR). Four hundred and-sixty five patients (263 male, 202 female; age, 72.47 ± 11.33 years) with suspected thoracic lesion(s) after the initial onsite analysis of CXR underwent DTS. Two independent readers prospectively analyzed in consensus CXR and DTS images on a picture archiving and communications system-integrated workstation and proposed a diagnosis according to a confidence score for each lesion: 1 or 2 = definite or probable pulmonary or pleural benign lesion or pseudolesion deserving no further diagnostic work-up; 3 = indeterminate; 4 or 5 = probable or definite pulmonary lesion deserving further diagnostic work-up by computed tomography (CT). In patients who did not undergo chest CT, the DTS findings had to be confirmed by 6 to 12 months' imaging follow-up. Finally, 229 pulmonary lesions (193 thoracic and 36 pleural lesions) and 236 pseudolesions were identified. Based on DTS images, readers correctly classified all pseudolesions except for 10/236 (reader 1) or 11/236 (reader 2) pseudolesions and 7 (reader 1) or 6 (reader 2) pulmonary subpleural lesions located in the anterior or posterior lung region close to the thoracic wall. Chest CT was performed in 127/465 (27%) patients, whereas in 338/465 patients (73%) CXR doubtful findings were resolved by DTS. DTS allowed to exclude most pseudolesions initially considered as potential thoracic lesions on the preliminary onsite assessment of CXR and allowed to exclude pulmonary lesions deserving CT assessment in about three fourths of the patients. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

  20. Comparative pulmonary toxicity of inhaled metalworking fluids in rats and mice.

    Science.gov (United States)

    Ryan, Kristen R; Cesta, Mark F; Herbert, Ronald; Brix, Amy; Cora, Michelle; Witt, Kristine; Kissling, Grace; Morgan, Daniel L

    2017-05-01

    Metalworking fluids (MWFs) are complex formulations designed for effective lubricating, cooling, and cleaning tools and parts during machining operations. Adverse health effects such as respiratory symptoms, dermatitis, and cancer have been reported in workers exposed to MWFs. Several constituents of MWFs have been implicated in toxicity and have been removed from the formulations over the years. However, animal studies with newer MWFs demonstrate that they continue to pose a health risk. This investigation examines the hypothesis that unrecognized health hazards exist in currently marketed MWF formulations that are presumed to be safe based on hazard assessments of individual ingredients. In vivo 13-week inhalation studies were designed to characterize and compare the potential toxicity of four MWFs: Trim VX, Cimstar 3800, Trim SC210, and Syntilo 1023. Male and female Wistar Han rats or Fischer 344N/Tac rats and B6C3F1/N mice were exposed to MWFs via whole-body inhalation at concentrations of 0, 25, 50, 100, 200, or 400 mg/m 3 for 13 weeks, after which, survival, body and organ weights, hematology and clinical chemistry, histopathology, and genotoxicity were assessed following exposure. Although high concentrations were used, survival was not affected and toxicity was primarily within the respiratory tract of male and female rats and mice. Minor variances in toxicity were attributed to differences among species as well as in the chemical components of each MWF. Pulmonary fibrosis was present only in rats and mice exposed to Trim VX. These data confirm that newer MWFs have the potential to cause respiratory toxicity in workers who are repeatedly exposed via inhalation.

  1. New evidence on the health hazards and control of metalworking fluids since completion of the OSHA advisory committee report.

    Science.gov (United States)

    Mirer, Franklin E

    2010-08-01

    Metalworking fluids (MWF) are used in the manufacture of engines, transmissions, chassis parts and other products. In 2003, OSHA denied a union petition to promulgate a standard for MWF. The 3rd Circuit Court of Appeals rejected a union lawsuit to compel OSHA to regulate MWF. OSHA relied exclusively on the 1999 Metal Working Fluids Standards Advisory Committee report, therefore, only evidence available before 1999 was quoted supporting the denial. This review was conducted to identify studies published since 1998. Electronic reference sources were queried for the terms for metalworking fluids, machining fluids, cutting fluids, cutting oils, coolants, machining, and machinist. All items returned were reviewed for relevance to MWF regulation. The review noted 227 reports in the peer reviewed literature directly relevant to regulation of MWF exposures. Of these, 26 addressed cancer; 58 respiratory effects; 32 skin effects or absorption; 45 microbial contaminants; and 76 exposure measurements and controls. Three major studies identified excess cancer including lung, liver, pancreatic, laryngeal, and leukemia associated with MWF exposures. Reports strengthened associations of asthma and hypersensitivity pneumonitis with recent exposure to MWF. Material new evidence demonstrates significant risks to material impairment of health at prevailing exposure levels and feasibility of lower exposure limits. Copyright 2010 Wiley-Liss, Inc.

  2. Solving Sudoku with Constraint Programming

    Science.gov (United States)

    Crawford, Broderick; Castro, Carlos; Monfroy, Eric

    Constraint Programming (CP) is a powerful paradigm for modeling and solving Complex Combinatorial Problems (generally issued from Decision Making). In this work, we model the known Sudoku puzzle as a Constraint Satisfaction Problems and solve it with CP comparing the performance of different Variable and Value Selection Heuristics in its Enumeration phase. We encourage this kind of benchmark problem because it may suggest new techniques in constraint modeling and solving of complex systems, or aid the understanding of its main advantages and limits.

  3. A novel technique based on the homotopy analysis method to solve the first kind Cauchy integral equations arising in the theory of airfoils

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Fariborzi Araghi

    2016-02-01

    Full Text Available In this paper, a new efficient and applicable method in order to solve the first kind Cauchy integral equation is presented. For this purpose, this integral equation is converted to the second kind, then the homotopy analysis method is applied to solve the obtained integral equation. Also, the convergence of the proposed method is proved. Several applicable examples are presented which are appeared in the theory of airfoils in fluid mechanics. By plotting the $\\hbar$-curves, we show the convergence region of the examples and the tables of absolute errors for different values of $\\hbar$ and $x$ are tabulated.

  4. How to solve mathematical problems

    CERN Document Server

    Wickelgren, Wayne A

    1995-01-01

    Seven problem-solving techniques include inference, classification of action sequences, subgoals, contradiction, working backward, relations between problems, and mathematical representation. Also, problems from mathematics, science, and engineering with complete solutions.

  5. Professional Teacher Education Module Series. Direct Students in Applying Problem-Solving Techniques, Module C-8 of Category C--Instructional Execution.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This eighth in a series of twenty-nine learning modules on instructional execution is designed to give secondary and postsecondary vocational teachers the background knowledge and experience needed to use problem solving as an instructional method in the classroom and laboratory. The terminal objective for the module is to direct students in…

  6. Employees Training Evaluation related to the Competency Standards in the Steel and Metalworking Industry in Boyacá, Colombia

    Directory of Open Access Journals (Sweden)

    Carlos Guillermo Carreno-Bodensiek

    2016-12-01

    Full Text Available This work presents the results of a research process applied to a sample of companies in the steel and metalworking sector in Boyacá, Colombia. The active workers are evaluated over the Occupational Competency Standards related to their daily activities. It also aims to highlight the formation priority of human talent for business, according to build up a level of competitiveness. Also, seeks to meet the need to train and develop skills and competencies in the workforce, taking into account the concepts of experts about training and developing proposals for management. This research is consistent with global trends in education and the requirements of standardization of training, why diagnoses and designs are focused on the functions of the companies related to the Standards of Competency.

  7. Susceptibility of Mycobacterium immunogenum and Pseudomonas fluorescens to formaldehyde and non-formaldehyde biocides in semi-synthetic metalworking fluids.

    Science.gov (United States)

    Selvaraju, Suresh B; Khan, Izhar U H; Yadav, Jagjit S

    2011-01-20

    Mycobacterium immunogenum, a newly identified member of the Mycobacterium chelonae_M. abscessus complex is considered a potential etiological agent for hypersensitivity pneumonitis (HP) in machine workers exposed to contaminated metalworking fluid (MWF). This study investigated the biocidal efficacy of the frequently applied commercial formaldehyde-releasing (HCHO) biocides Grotan and Bioban CS 1135 and non-HCHO type biocides Kathon 886 MW (isothiazolone) and Preventol CMK 40 (phenolic) toward this emerging mycobacterial species (M. immunogenum) in HP-linked MWFs, alone and in presence of a representative of the Gram-negative bacterial contaminants, Pseudomonas fluorescens, using two semi-synthetic MWF matrices (designated Fluid A and Fluid B). Relative biocide susceptibility analysis indicated M immunogenum to be comparatively more resistant (2-1600 fold) than P. fluorescens to the tested biocides under the varied test conditions. In terms of minimum inhibitory concentration, Kathon was the most effective biocide against M. immunogenum. Fluid factors had a major effect on the biocide susceptibility. Fluid A formulation provided greater protective advantage to the test organisms than Fluid B. Fluid dialysis (Fluid A) led to an increased biocidal efficacy of Grotan, Kathon and Preventol against M. immunogenum further implying the role of native fluid components. Used fluid matrix, in general, increased the resistance of the two test organisms against the biocides, with certain exceptions. M. immunogenum resistance increased in presence of the co-contaminant P. fluorescens. Collectively, the results show a multifactorial nature of the biocide susceptibility of MWF-colonizing mycobacteria and highlight the importance of more rigorous efficacy testing and validation of biocides prior to and during their application in metalworking fluid operations.

  8. Susceptibility of Mycobacterium immunogenum and Pseudomonas fluorescens to Formaldehyde and Non-Formaldehyde Biocides in Semi-Synthetic Metalworking Fluids

    Directory of Open Access Journals (Sweden)

    Suresh B. Selvaraju

    2011-01-01

    Full Text Available Mycobacterium immunogenum, a newly identified member of the Mycobacterium chelonae_M. abscessus complex is considered a potential etiological agent for hypersensitivity pneumonitis (HP in machine workers exposed to contaminated metalworking fluid (MWF. This study investigated the biocidal efficacy of the frequently applied commercial formaldehyde-releasing (HCHO biocides Grotan and Bioban CS 1135 and non-HCHO type biocides Kathon 886 MW (isothiazolone and Preventol CMK 40 (phenolic toward this emerging mycobacterial species (M. immunogenum in HP-linked MWFs, alone and in presence of a representative of the Gram-negative bacterial contaminants, Pseudomonas fluorescens, using two semi-synthetic MWF matrices (designated Fluid A and Fluid B. Relative biocide susceptibility analysis indicated M immunogenum to be comparatively more resistant (2–1600 fold than P. fluorescens to the tested biocides under the varied test conditions. In terms of minimum inhibitory concentration, Kathon was the most effective biocide against M. immunogenum. Fluid factors had a major effect on the biocide susceptibility. Fluid A formulation provided greater protective advantage to the test organisms than Fluid B. Fluid dialysis (Fluid A led to an increased biocidal efficacy of Grotan, Kathon and Preventol against M. immunogenum further implying the role of native fluid components. Used fluid matrix, in general, increased the resistance of the two test organisms against the biocides, with certain exceptions. M. immunogenum resistance increased in presence of the co-contaminant P. fluorescens. Collectively, the results show a multifactorial nature of the biocide susceptibility of MWF-colonizing mycobacteria and highlight the importance of more rigorous efficacy testing and validation of biocides prior to and during their application in metalworking fluid operations.

  9. Mortality studies of metalworking fluid exposure in the automobile industry: VI. A case-control study of esophageal cancer.

    Science.gov (United States)

    Sullivan, P A; Eisen, E A; Woskie, S R; Kriebel, D; Wegman, D H; Hallock, M F; Hammond, S K; Tolbert, P E; Smith, T J; Monson, R R

    1998-07-01

    Results are reported from a nested case-control study of 60 esophageal cancer deaths among 46,384 automobile manufacturing workers potentially exposed to metalworking fluids (MWF) in machining and grinding operations. By using incidence-density sampling, controls were selected with a sampling ratio of 20:1 from among co-workers who remained at risk by the age of death of the case, matched on race, gender, plant, and year of birth. Conditional logistic regression was used to evaluate the risk associated with cumulative exposure (mg/m3-years) to each of three types of metalworking fluid (straight, soluble, and synthetic MWF), as well as with years of exposure to selected components of MWF, including nitrosamines, sulfur, biocides, and several metals. Esophageal cancer was found to be significantly associated with exposure to both soluble and synthetic MWF in grinding operations. The odds ratios (ORs) for grinding with soluble MWF were elevated at 2.5 or greater in all categories of cumulative exposure, although the exposure-response trend was statistically significant only when exposure was measured as duration. Those with 12 or more years exposure to soluble MWF in grinding operations experienced a 9.3-fold relative risk of esophageal cancer mortality (95% CI = 2.1-42.1). The OR for ever grinding with synthetic MWF was 4.1 (95% CI = 1.1-15.0). Elevated risk was also associated with two agents found in both synthetic and soluble fluids, nitrosamines, and biocides. For exposure to nitrosamines, the OR was 5.4 (95% CI = 1.5-19.9); for biocides the OR was 3.8 (95% CI = 0.8-18.9). However, because the same workers were exposed to grinding with synthetics, nitrosamines and biocides, it was not possible to separate the specific risks associated with these components.

  10. Biocidal Activity of Formaldehyde and Nonformaldehyde Biocides toward Mycobacterium immunogenum and Pseudomonas fluorescens in Pure and Mixed Suspensions in Synthetic Metalworking Fluid and Saline

    OpenAIRE

    Selvaraju, Suresh B.; Khan, Izhar U. H.; Yadav, Jagjit S.

    2005-01-01

    The microbicidal activity of four different biocides was studied in synthetic metalworking fluid (MWF) against Mycobacterium immunogenum, a suspected causative agent for hypersensitivity pneumonitis, and Pseudomonas fluorescens, a representative for the predominant gram-negative bacterial contaminants of MWF. The results indicated that M. immunogenum is more resistant than P. fluorescens to the tested formaldehyde-releasing biocides (Grotan and Bioban), isothiazolone (Kathon), and phenolic bi...

  11. Evaluating the use of zinc oxide and titanium dioxide nanoparticles in a metalworking fluid from a toxicological perspective

    Energy Technology Data Exchange (ETDEWEB)

    Seyedmahmoudi, S. H. [Oregon State University, Industrial Sustainability Laboratory, School of Mechanical, Industrial, and Manufacturing Engineering (United States); Harper, Stacey L. [Oregon State University, Department of Environmental and Molecular Toxicology & School of Chemical, Biological and Environmental Engineering (United States); Weismiller, Michael C. [Master Chemical Corporation (United States); Haapala, Karl R., E-mail: karl.haapala@oregonstate.edu [Oregon State University, Industrial Sustainability Laboratory, School of Mechanical, Industrial, and Manufacturing Engineering (United States)

    2015-02-15

    Adding nanoparticles (NPs) to metalworking fluids (MWFs) has been shown to improve performance in metal cutting. Zinc oxide nanoparticles (ZnO NPs) and titanium dioxide nanoparticles (TiO{sub 2} NPs), for example, have exhibited the ability to improve lubricant performance, decrease the heat created by machining operations, reduce friction and wear, and enhance thermal conductivity. ZnO and TiO{sub 2} NPs are also relatively inexpensive compared to many other NPs. Precautionary concerns of human health risks and environmental impacts, however, are especially important when adding NPs to MWFs. The goal of this research is to investigate the potential environmental and human health effects of these nanoenabled products during early design and development. This research builds on a prior investigation of the stability and toxicity characteristics of NPs used in metalworking nanofluids (MWnF™). The previous study only investigated one type of NP at one level of concentration. This research expands on the previous investigations through the valuation of three different types of NPs that vary in morphology (size and shape) and was conducted over a wide range of concentrations in the base fluid. In the presented work, mixtures of a microemulsion (TRIM{sup ®} MicroSol{sup ®} 585XT), two different types of TiO{sub 2} NPs (referred to as TiO{sub 2}A and TiO{sub 2}B) and one type of ZnO NP were used to evaluate MWnF™ stability and toxicity. Dynamic light scattering was used to assess stability over time and an embryonic zebrafish assay was used to assess toxicological impacts. The results reveal that, in general, the addition of these NPs increased toxicity relative to the NP-free formulation. The lowest rate of zebrafish malformations occurred at 5 g/L TiO{sub 2}A NP, which was even lower than for the base fluid. This result is particularly promising for future MWnF™ development, given that the mortality rate for 5 g/L TiO{sub 2}A was not significantly different

  12. Assessment of the toxicity of wastewater from the metalworking industry treated using a conventional physico-chemical process.

    Science.gov (United States)

    Machado, Rodrigo Matuella; Monteggia, Luiz Olinto; Arenzon, Alexandre; Curia, Ana Cristina

    2016-06-01

    This article presents results from a toxicity reduction evaluation program intended to describe wastewater from the metalworking industry that was treated using a conventional physico-chemical process. The toxicity of the wastewater for the microcrustacean Daphnia magna was predominantly expressive. Alkaline cyanide wastewater generated from electroplating accounted for the largest number of samples with expressive toxicity. When the raw wastewater concentrations in the batches were repeated, inexpressive toxicity variations were observed more frequently among the coagulated-flocculated samples. At the coagulation-flocculation step, 22.2 % of the treatments had reduced acute toxicity, 30.6 % showed increased toxicity, and 47.2 % remained unchanged. The conductivity and total dissolved solids contents of the wastewater indicated the presence of salts with charges that were inappropriate for the survival of daphnid. The wastewaters treated by neutralization and coagulation-flocculation had average metallic compound contents that were greater than the reference toxic concentrations reported in other studies, suggesting that metals likely contributed to the toxic effects of the wastewater on freshwater microcrustaceans. Thus, alternative coagulants and flocculants should be assessed, and feasible doses should be determined to improve wastewater treatment. In addition, advanced treatment processes should be assessed for their abilities to remove dissolved toxic salts and ions.

  13. QUALITY OF LIFE AT WORK: A STUDY OF WORKERS IN THE METALWORKING INDUSTRY IN THE MIDWEST OF SANTA CATARINA

    Directory of Open Access Journals (Sweden)

    G. Lunardelli

    2017-08-01

    Full Text Available This study aimed to evaluate the quality of life of workers in the metalworking industry in the middle west of Santa Catarina. Therefore, we opted for a qualitative approach to know the aspects that guide and characterize female employment in the labor market, and was carried out a survey to know the reality faced by this group. It is important to emphasize the importance of companies adopt different methods and practices to adapt the working environment and conditions provide rights similar to those of men. Thus, the article addressed the inclusion of women in the workplace, treating the historical context of the feminization of the labor market, the gender division and inequality between genders in this sector. Still, women's insertion in the mechanical metal sector in the middle West Santa Catarina region was analyzed, and the preservation of their rights and appreciation while working. Although women have gained greater participation within organizations, they face wage differences, behavioral and quality of life that need to be better studied.

  14. Pre-Service Class Teacher' Ability in Solving Mathematical Problems and Skills in Solving Daily Problems

    Science.gov (United States)

    Aljaberi, Nahil M.; Gheith, Eman

    2016-01-01

    This study aims to investigate the ability of pre-service class teacher at University of Petrain solving mathematical problems using Polya's Techniques, their level of problem solving skills in daily-life issues. The study also investigates the correlation between their ability to solve mathematical problems and their level of problem solving…

  15. Flow Cytometry Is a Powerful Tool for Assessment of the Viability of Fungal Conidia in Metalworking Fluids.

    Science.gov (United States)

    Vanhauteghem, D; Demeyere, K; Callaert, N; Boelaert, A; Haesaert, G; Audenaert, K; Meyer, E

    2017-08-15

    Fungal contamination of metalworking fluids (MWF) is a dual problem in automated processing plants because resulting fungal biofilms obstruct cutting, drilling, and polishing machines. Moreover, some fungal species of MWF comprise pathogens such as Fusarium solani Therefore, the development of an accurate analytical tool to evaluate conidial viability in MWF is important. We developed a flow cytometric method to measure fungal viability in MWF using F. solani as the model organism. To validate this method, viable and dead conidia were mixed in several proportions and flow was cytometrically analyzed. Subsequently, we assessed the fungicidal activity of two commercial MWF using flow cytometry (FCM) and compared it with microscopic analyses and plating experiments. We evaluated the fungal growth in both MWF after 7 days using quantitative PCR (qPCR) to assess the predictive value of FCM. Our results showed that FCM distinguishes live from dead conidia as early as 5 h after exposure to MWF, whereas the microscopic germination approach detected conidial viability much later and less accurately. At 24 h, microscopic analyses of germinating conidia and live/dead analyses by FCM correlated well, although the former consistently underestimated the proportion of viable conidia. In addition, the reproducibility and sensitivity of the flow cytometric method were high and allowed assessment of the fungicidal properties of two commercial MWF. Importantly, the obtained flow cytometric results on viability of F. solani conidia at both early time points (5 h and 24 h) correlated well with fungal biomass measurements assessed via a qPCR methodology 7 days after the start of the experiment. IMPORTANCE This result shows the predictive power of flow cytometry (FCM) in assessing the fungicidal capacity of MWF formulations. It also implies that FCM can be implemented as a rapid detection tool to estimate the viable fungal load in an industrial processing matrix (MWF). Copyright © 2017

  16. A technique for determining the optimum mix of logistics service providers of a make-to-order supply chain by formulating and solving a constrained nonlinear cost optimization problem

    Directory of Open Access Journals (Sweden)

    Mrityunjoy Roy

    2013-04-01

    Full Text Available In this paper, a technique has been developed to determine the optimum mix of logistic service providers of a make-to-order (MTO supply chain. A serial MTO supply chain with different stages/ processes has been considered. For each stage different logistic service providers with different mean processing lead times, but same lead time variances are available. A realistic assumption that for each stage, the logistic service provider who charges more for his service consumes less processing lead time and vice-versa has been made in our study. Thus for each stage, for each service provider, a combination of cost and mean processing lead time is available. Using these combinations, for each stage, a polynomial curve, expressing cost of that stage as a function of mean processing lead time is fit. Cumulating all such expressions of cost for the different stages along with incorporation of suitable constraints arising out of timely delivery, results in the formulation of a constrained nonlinear cost optimization problem. On solving the problem using mathematica, optimum processing lead time for each stage is obtained. Using these optimum processing lead times and by employing a simple technique the optimum logistic service provider mix of the supply chain along with the corresponding total cost of processing is determined. Finally to examine the effect of changes in different parameters on the optimum total processing cost of the supply chain, sensitivity analysis has been carried out graphically.

  17. Distributed Problem-Solving

    DEFF Research Database (Denmark)

    Chemi, Tatiana

    2016-01-01

    a perspective that is relevant to higher education. The focus here is on how artists solve problems in distributed paths, and on the elements of creative collaboration. Creative problem-solving will be looked at as an ongoing dialogue that artists engage with themselves, with others, with recipients......, what can educators at higher education learn from the ways creative groups solve problems? How can artists contribute to inspiring higher education?...

  18. Methods of solving nonstandard problems

    CERN Document Server

    Grigorieva, Ellina

    2015-01-01

    This book, written by an accomplished female mathematician, is the second to explore nonstandard mathematical problems – those that are not directly solved by standard mathematical methods but instead rely on insight and the synthesis of a variety of mathematical ideas.   It promotes mental activity as well as greater mathematical skills, and is an ideal resource for successful preparation for the mathematics Olympiad. Numerous strategies and techniques are presented that can be used to solve intriguing and challenging problems of the type often found in competitions.  The author uses a friendly, non-intimidating approach to emphasize connections between different fields of mathematics and often proposes several different ways to attack the same problem.  Topics covered include functions and their properties, polynomials, trigonometric and transcendental equations and inequalities, optimization, differential equations, nonlinear systems, and word problems.   Over 360 problems are included with hints, ...

  19. 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...

  20. Teaching Creative Problem Solving.

    Science.gov (United States)

    Christensen, Kip W.; Martin, Loren

    1992-01-01

    Interpersonal and cognitive skills, adaptability, and critical thinking can be developed through problem solving and cooperative learning in technology education. These skills have been identified as significant needs of the workplace as well as for functioning in society. (SK)

  1. Electromagnetic Hammer for Metalworking

    Science.gov (United States)

    Anderson, S. A.; Brunet, F.; Dowd, A.; Durham, R.; Ezell, J.; Gorr, G.; Hartley, D.; Jackson, F.; Marchand, J.; Macfarlane, W.; hide

    1986-01-01

    High eddy currents apply pressure for cold-forming. Coil housing constructed for mechanical strength to hold coil against magnetic force, to maintain electrical contact with coil ends, and to maintain insulation between coil turns. Drilled holes placed to facilitate release of bubbles during potting. In contrast with mechanical hammers, electromagnetic hammer requires no dynamic material contact with workpiece; consequently, produces almost no change in metal grain structure.

  2. Adaptive Problem Solving

    Science.gov (United States)

    2017-03-01

    1) problem solving architecture; (2) problem representation ; (3) heuristics and control knowledge ; and (4) algorithms. In the area of problem... language which humans use to describe problems/domains and SAS+ is a standard problem representation input language used by many planners. Given a...implemented a system, MSP, that given a specific problem, automatically generates, evaluates, and assembles different combinations of representations and

  3. Electric Current Solves Mazes

    Science.gov (United States)

    Ayrinhac, Simon

    2014-01-01

    We present in this work a demonstration of the maze-solving problem with electricity. Electric current flowing in a maze as a printed circuit produces Joule heating and the right way is instantaneously revealed with infrared thermal imaging. The basic properties of electric current can be discussed in this context, with this challenging question:…

  4. Solving a binary puzzle

    NARCIS (Netherlands)

    P.H. Utomo (Putranto); R.H. Makarim (Rusydi)

    2017-01-01

    textabstractA Binary puzzle is a Sudoku-like puzzle with values in each cell taken from the set (Formula presented.). Let (Formula presented.) be an even integer, a solved binary puzzle is an (Formula presented.) binary array that satisfies the following conditions: (1) no three consecutive ones and

  5. On Solving Linear Recurrences

    Science.gov (United States)

    Dobbs, David E.

    2013-01-01

    A direct method is given for solving first-order linear recurrences with constant coefficients. The limiting value of that solution is studied as "n to infinity." This classroom note could serve as enrichment material for the typical introductory course on discrete mathematics that follows a calculus course.

  6. Solving Problems through Circles

    Science.gov (United States)

    Grahamslaw, Laura; Henson, Lisa H.

    2015-01-01

    Several problem-solving interventions that utilise a "circle" approach have been applied within the field of educational psychology, for example, Circle Time, Circle of Friends, Sharing Circles, Circle of Adults and Solution Circles. This research explored two interventions, Solution Circles and Circle of Adults, and used thematic…

  7. Solving Environmental Problems

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders; Sofka, Wolfgang; Grimpe, Christoph

    2017-01-01

    dispersed. Hence, firms need to collaborate. We shed new light on collaborative search strategies led by firms in general and for solving environmental problems in particular. Both topics are largely absent in the extant open innovation literature. Using data from the European Seventh Framework Program...... for Research and Technological Development (FP7), our results indicate that the problem-solving potential of a search strategy increases with the diversity of existing knowledge of the partners in a consortium and with the experience of the partners involved. Moreover, we identify a substantial negative effect......Recent innovation and strategy research emphasizes the importance of firm’s search for external knowledge to improve innovation performance. We focus on such search strategies within the domain of sustainable innovation in which problems are inherently complex and the relevant knowledge is widely...

  8. Appreciative Problem Solving

    DEFF Research Database (Denmark)

    Hansen, David

    2012-01-01

    Many industrial production work systems have increased in complexity, and their new business model scompete on innovation, rather than low cost.At a medical device production facility committed to Lean Production, a research project was carried out to use Appreciative Inquiry to better engage...... employee strengths in continuou simprovements of the work system. The research question was: “How can Lean problem solving and Appreciative Inquiry be combined for optimized work system innovation?” The research project was carried out as a co-creation process with close cooperation between researcher...... to work system innovation and discusses how Appreciative Inquiry, Problem Solving, and the combination ‘Appreciative Problem Solving’ can be used to optimize continuous work system innovation.These findings add to the theoretical foundation of the emerging field of Strength-based Lean....

  9. Simon on problem solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2006-01-01

    as a general approach to problem solving. We apply these Simonian ideas to organisational issues, specifically new organisational forms. Specifically, Simonian ideas allow us to develop a morphology of new organisational forms and to point to some design problems that characterise these forms.......Two of Herbert Simon's best-known papers are 'The Architecture of Complexity' and 'The Structure of Ill-Structured Problems.' We discuss the neglected links between these two papers, highlighting the role of decomposition in the context of problems on which constraints have been imposed...

  10. Clarification and filtration of the floculated partuicles suspension from a chemical treatment of waste oil-in-water emulsions from a non-ferrous metalworking plant

    Directory of Open Access Journals (Sweden)

    Lazarević Vesna B.

    2011-01-01

    Full Text Available The effects of the coagulation/floculation conditions on clarification and filtration of the floculated particle suspension obtained by the chemical treatment of the waste oil-in-water emulsion (OWE from a non-ferrous metalworking plant were studied. The treatment involved the addition of aluminum(III sulfate and lime to the OWE. The main goal was to define the optimum conditions for clarification and filtration of the floculated particle suspension. The factors involved were amounts lime (i.e. pH and filter aid added the OWE on clarification and filtration rates. At pH>10, the clarification rate was increased and the final volume of the concentrated suspension (sludge was reduced, while filter aid affected negatively the clarification rate. The filtration rate was also increased when the coagulation was carried out at pH>10. The floculated particle suspension should be concentrated before filtration in order to decrease the filtration duration. The most efficient filter aid was Celite standard super-cel, its optimum initial concentration being found to be 2 g/dm3.

  11. Occupational exposure to mineral oil metalworking fluid (MWFs) mist: Development of new methodologies for mist sampling and analysis. Results from an inter-laboratory comparison

    International Nuclear Information System (INIS)

    Huynh, C Khanh; Herrera, H; Parrat, J; Wolf, R; Perret, V

    2009-01-01

    Metalworking Fluids (MWFs) are largely used in the sector of undercutting, a large professional activity in Switzerland, in particular in the fine mechanic and watch making industry. France proposes a Permissible Exposure Limit (PEL) of 1 mg.m -3 of aerosol. The American Conference of Governmental Industrial Hygienists (ACGIH) sets its value at 5 mg.m -3 but a proposal to lower the standard ('intended changes') to 0.2 mg.m -3 of aerosol is pending since 2001. However, it has not become a recognized threshold limit value for exposure. Since 2003, the new Swiss PEL (MAK) recommendations would be 0.2 mg.m -3 of aerosol (oil with boiling point > 350 deg. C without additives) and/or 20 mg.m -3 of oil aerosol + vapour for medium or light oil. To evaluate evaporative losses of sampled oil, the German 'Berufsgenossenschaftliches Institut fuer Arbeitssicherheit' (BGIA) recommends the use of a XAD-2 cartridge behind the filter. The method seems to work perfectly for MWFs in a clean occupational atmosphere free from interference of light vapour cleaning solvent such as White Spirit. But, in real situation, machine shop atmosphere contaminated with traces of White Spirit, the BGIA method failed to estimate the MWFs levels (over-estimation). In this paper, we propose a new approach meant to measure both oil vapours and aerosols. Five inter-laboratory comparisons are discussed, based on the production of oil mist in an experimental chamber under controlled conditions.

  12. Solving Differential Equations in R: Package deSolve

    NARCIS (Netherlands)

    Soetaert, K.E.R.; Petzoldt, T.; Setzer, R.W.

    2010-01-01

    In this paper we present the R package deSolve to solve initial value problems (IVP) written as ordinary differential equations (ODE), differential algebraic equations (DAE) of index 0 or 1 and partial differential equations (PDE), the latter solved using the method of lines approach. The

  13. Solved problems in electromagnetics

    CERN Document Server

    Salazar Bloise, Félix; Bayón Rojo, Ana; Gascón Latasa, Francisco

    2017-01-01

    This book presents the fundamental concepts of electromagnetism through problems with a brief theoretical introduction at the beginning of each chapter. The present book has a strong  didactic character. It explains all the mathematical steps and the theoretical concepts connected with the development of the problem. It guides the reader to understand the employed procedures to learn to solve the exercises independently. The exercises are structured in a similar way: The chapters begin with easy problems increasing progressively in the level of difficulty. This book is written for students of physics and engineering in the framework of the new European Plans of Study for Bachelor and Master and also for tutors and lecturers. .

  14. Solved problems in electrochemistry

    International Nuclear Information System (INIS)

    Piron, D.L.

    2004-01-01

    This book presents calculated solutions to problems in fundamental and applied electrochemistry. It uses industrial data to illustrate scientific concepts and scientific knowledge to solve practical problems. It is subdivided into three parts. The first uses modern basic concepts, the second studies the scientific basis for electrode and electrolyte thermodynamics (including E-pH diagrams and the minimum energy involved in transformations) and the kinetics of rate processes (including the energy lost in heat and in parasite reactions). The third part treats larger problems in electrolysis and power generation, as well as in corrosion and its prevention. Each chapter includes three sections: the presentation of useful principles; some twenty problems with their solutions; and, a set of unsolved problems

  15. Methods of solving sequence and series problems

    CERN Document Server

    Grigorieva, Ellina

    2016-01-01

    This book aims to dispel the mystery and fear experienced by students surrounding sequences, series, convergence, and their applications. The author, an accomplished female mathematician, achieves this by taking a problem solving approach, starting with fascinating problems and solving them step by step with clear explanations and illuminating diagrams. The reader will find the problems interesting, unusual, and fun, yet solved with the rigor expected in a competition. Some problems are taken directly from mathematics competitions, with the name and year of the exam provided for reference. Proof techniques are emphasized, with a variety of methods presented. The text aims to expand the mind of the reader by often presenting multiple ways to attack the same problem, as well as drawing connections with different fields of mathematics. Intuitive and visual arguments are presented alongside technical proofs to provide a well-rounded methodology. With nearly 300 problems including hints, answers, and solutions,Met...

  16. Computer Problem-Solving Coaches

    Science.gov (United States)

    Hsu, Leon; Heller, Kenneth

    2005-09-01

    Computers might be able to play an important role in physics instruction by coaching students to develop good problem-solving skills. Building on previous research on student problem solving and on designing computer programs to teach cognitive skills, we are developing a prototype computer coach to provide students with guided practice in solving problems. In addition to helping students become better problem solvers, such programs can be useful in studying how students learn to solve problems and how and if problem-solving skills can be transferred from a computer to a pencil-and-paper environment.

  17. Insightful problem solving in an Asian elephant.

    Directory of Open Access Journals (Sweden)

    Preston Foerder

    Full Text Available The "aha" moment or the sudden arrival of the solution to a problem is a common human experience. Spontaneous problem solving without evident trial and error behavior in humans and other animals has been referred to as insight. Surprisingly, elephants, thought to be highly intelligent, have failed to exhibit insightful problem solving in previous cognitive studies. We tested whether three Asian elephants (Elephas maximus would use sticks or other objects to obtain food items placed out-of-reach and overhead. Without prior trial and error behavior, a 7-year-old male Asian elephant showed spontaneous problem solving by moving a large plastic cube, on which he then stood, to acquire the food. In further testing he showed behavioral flexibility, using this technique to reach other items and retrieving the cube from various locations to use as a tool to acquire food. In the cube's absence, he generalized this tool utilization technique to other objects and, when given smaller objects, stacked them in an attempt to reach the food. The elephant's overall behavior was consistent with the definition of insightful problem solving. Previous failures to demonstrate this ability in elephants may have resulted not from a lack of cognitive ability but from the presentation of tasks requiring trunk-held sticks as potential tools, thereby interfering with the trunk's use as a sensory organ to locate the targeted food.

  18. Solving the Antibiotic Crisis.

    Science.gov (United States)

    Wright, Gerard D

    2015-02-13

    Antibiotics are essential for both treating and preventing infectious diseases. Paradoxically, despite their importance as pillars of modern medicine, we are in danger of losing antibiotics because of the evolution and dissemination of resistance mechanisms throughout all pathogenic microbes. This fact, coupled with an inability to bring new drugs to market at a pace that matches resistance, has resulted in a crisis of global proportion. Solving this crisis requires the actions of many stakeholders, but chemists, chemical biologists, and microbiologists must drive the scientific innovation that is required to maintain our antibiotic arsenal. This innovation requires (1) a deep understanding of the evolution and reservoirs of resistance; (2) full knowledge of the molecular mechanisms of antibiotic action and resistance; (3) the discovery of chemical and genetic probes of antibiotic action and resistance; (4) the integration of systems biology into antibiotic discovery; and (5) the discovery of new antimicrobial chemical matter. Addressing these pressing scientific gaps will ensure that we can meet the antibiotic crisis with creativity and purpose.

  19. Spectral difference methods for solving differential equations

    Science.gov (United States)

    Mazziotti, David A.

    1999-01-01

    A family of recently developed techniques is explored for achieving both matrix sparsity and rapid convergence when numerically solving differential and eigenvalue equations without domain decomposition. These methods, which we call spectral differences, include Boyd's sum acceleration techniques and the Lagrange distributed approximating functional (LDAF) approach. A formula is developed for estimating the unknown Gaussian parameter within LDAF. We implement these methods to calculate the Morse vibrational energies for diatomic iodine. For equivalent bandwidths the sum acceleration with finite difference weights generates energies which are between two and three orders of magnitude more accurate than those from LDAF.

  20. A comparison of the Method of Lines to finite difference techniques in solving time-dependent partial differential equations. [with applications to Burger equation and stream function-vorticity problem

    Science.gov (United States)

    Kurtz, L. A.; Smith, R. E.; Parks, C. L.; Boney, L. R.

    1978-01-01

    Steady state solutions to two time dependent partial differential systems have been obtained by the Method of Lines (MOL) and compared to those obtained by efficient standard finite difference methods: (1) Burger's equation over a finite space domain by a forward time central space explicit method, and (2) the stream function - vorticity form of viscous incompressible fluid flow in a square cavity by an alternating direction implicit (ADI) method. The standard techniques were far more computationally efficient when applicable. In the second example, converged solutions at very high Reynolds numbers were obtained by MOL, whereas solution by ADI was either unattainable or impractical. With regard to 'set up' time, solution by MOL is an attractive alternative to techniques with complicated algorithms, as much of the programming difficulty is eliminated.

  1. Multiscale empirical interpolation for solving nonlinear PDEs

    KAUST Repository

    Calo, Victor M.

    2014-12-01

    In this paper, we propose a multiscale empirical interpolation method for solving nonlinear multiscale partial differential equations. The proposed method combines empirical interpolation techniques and local multiscale methods, such as the Generalized Multiscale Finite Element Method (GMsFEM). To solve nonlinear equations, the GMsFEM is used to represent the solution on a coarse grid with multiscale basis functions computed offline. Computing the GMsFEM solution involves calculating the system residuals and Jacobians on the fine grid. We use empirical interpolation concepts to evaluate these residuals and Jacobians of the multiscale system with a computational cost which is proportional to the size of the coarse-scale problem rather than the fully-resolved fine scale one. The empirical interpolation method uses basis functions which are built by sampling the nonlinear function we want to approximate a limited number of times. The coefficients needed for this approximation are computed in the offline stage by inverting an inexpensive linear system. The proposed multiscale empirical interpolation techniques: (1) divide computing the nonlinear function into coarse regions; (2) evaluate contributions of nonlinear functions in each coarse region taking advantage of a reduced-order representation of the solution; and (3) introduce multiscale proper-orthogonal-decomposition techniques to find appropriate interpolation vectors. We demonstrate the effectiveness of the proposed methods on several nonlinear multiscale PDEs that are solved with Newton\\'s methods and fully-implicit time marching schemes. Our numerical results show that the proposed methods provide a robust framework for solving nonlinear multiscale PDEs on a coarse grid with bounded error and significant computational cost reduction.

  2. Difficulties in Genetics Problem Solving.

    Science.gov (United States)

    Tolman, Richard R.

    1982-01-01

    Examined problem-solving strategies of 30 high school students as they solved genetics problems. Proposes a new sequence of teaching genetics based on results: meiosis, sex chromosomes, sex determination, sex-linked traits, monohybrid and dihybrid crosses (humans), codominance (humans), and Mendel's pea experiments. (JN)

  3. Problem Solving in the Professions.

    Science.gov (United States)

    Jackling, Noel; And Others

    1990-01-01

    It is proposed that algorithms and heuristics are useful in improving professional problem-solving abilities when contextualized within the academic discipline. A basic algorithm applied to problem solving in undergraduate engineering education and a similar algorithm applicable to legal problems are used as examples. Problem complexity and…

  4. Combinatorial reasoning to solve problems

    NARCIS (Netherlands)

    Coenen, Tom Johannes Maria; Hof, Frits; Verhoef, Neeltje Cornelia

    2016-01-01

    This study reports combinatorial reasoning to solve problems. We observed the mathematical thinking of students aged 14-16. We study the variation of the students’ solution strategies in the context of emergent modelling. The results show that the students are tempted to begin the problem solving

  5. Solving the Stokes problem on a massively parallel computer

    DEFF Research Database (Denmark)

    Axelsson, Owe; Barker, Vincent A.; Neytcheva, Maya

    2001-01-01

    We describe a numerical procedure for solving the stationary two‐dimensional Stokes problem based on piecewise linear finite element approximations for both velocity and pressure, a regularization technique for stability, and a defect‐correction technique for improving accuracy. Eliminating...... boundary value problem for each velocity component, are solved by the conjugate gradient method with a preconditioning based on the algebraic multi‐level iteration (AMLI) technique. The velocity is found from the computed pressure. The method is optimal in the sense that the computational work...... the velocity unknowns from the algebraic system yields a symmetric positive semidefinite system for pressure which is solved by an inner‐outer iteration. The outer iterations consist of the unpreconditioned conjugate gradient method. The inner iterations, each of which corresponds to solving an elliptic...

  6. Creative problem solving: an applied university course

    Directory of Open Access Journals (Sweden)

    René Victor Valqui Vidal

    2010-08-01

    Full Text Available This paper presents the principles of active learning and the contents of a creativity course entitled: Creativity and Problem Solving. The main purpose of this course is to create a space to discuss, reflect and experiment with creativity, creative processes and creative tools of relevance for students of any speciality (60% will end as operational researchers working with problem solving approaches. This course has run with big success since 1998 at the Technical University of Denmark. It started with very few students, now is a very popular course attracting many students from abroad. The selected themes, the methods and techniques, the structure of this course, the learning processes and the achieved results are presented. The results of student's and teacher's evaluations are also outlined. Finally some reflections, recommendations and conclusions are discussed.

  7. Solving ptychography with a convex relaxation

    Science.gov (United States)

    Horstmeyer, Roarke; Chen, Richard Y.; Ou, Xiaoze; Ames, Brendan; Tropp, Joel A.; Yang, Changhuei

    2015-05-01

    Ptychography is a powerful computational imaging technique that transforms a collection of low-resolution images into a high-resolution sample reconstruction. Unfortunately, algorithms that currently solve this reconstruction problem lack stability, robustness, and theoretical guarantees. Recently, convex optimization algorithms have improved the accuracy and reliability of several related reconstruction efforts. This paper proposes a convex formulation of the ptychography problem. This formulation has no local minima, it can be solved using a wide range of algorithms, it can incorporate appropriate noise models, and it can include multiple a priori constraints. The paper considers a specific algorithm, based on low-rank factorization, whose runtime and memory usage are near-linear in the size of the output image. Experiments demonstrate that this approach offers a 25% lower background variance on average than alternating projections, the ptychographic reconstruction algorithm that is currently in widespread use.

  8. Students’ Covariational Reasoning in Solving Integrals’ Problems

    Science.gov (United States)

    Harini, N. V.; Fuad, Y.; Ekawati, R.

    2018-01-01

    Covariational reasoning plays an important role to indicate quantities vary in learning calculus. This study investigates students’ covariational reasoning during their studies concerning two covarying quantities in integral problem. Six undergraduate students were chosen to solve problems that involved interpreting and representing how quantities change in tandem. Interviews were conducted to reveal the students’ reasoning while solving covariational problems. The result emphasizes that undergraduate students were able to construct the relation of dependent variables that changes in tandem with the independent variable. However, students faced difficulty in forming images of continuously changing rates and could not accurately apply the concept of integrals. These findings suggest that learning calculus should be increased emphasis on coordinating images of two quantities changing in tandem about instantaneously rate of change and to promote conceptual knowledge in integral techniques.

  9. Solving complex fisheries management problems

    DEFF Research Database (Denmark)

    Petter Johnsen, Jahn; Eliasen, Søren Qvist

    2011-01-01

    A crucial issue for the new EU common fisheries policy is how to solve the discard problem. Through a study of the institutional set up and the arrangements for solving the discard problem in Denmark, the Faroe Islands, Iceland and Norway, the article identifies the discard problem as related to ...... to both natural, other material and to cultural conditions. Hence, solving the discard problem requires not only technical and regulatory instruments, but also arenas and structures that allow and facilitate processes of cultural change....

  10. Pulsating Star Mystery Solved

    Science.gov (United States)

    2010-11-01

    By discovering the first double star where a pulsating Cepheid variable and another star pass in front of one another, an international team of astronomers has solved a decades-old mystery. The rare alignment of the orbits of the two stars in the double star system has allowed a measurement of the Cepheid mass with unprecedented accuracy. Up to now astronomers had two incompatible theoretical predictions of Cepheid masses. The new result shows that the prediction from stellar pulsation theory is spot on, while the prediction from stellar evolution theory is at odds with the new observations. The new results, from a team led by Grzegorz Pietrzyński (Universidad de Concepción, Chile, Obserwatorium Astronomiczne Uniwersytetu Warszawskiego, Poland), appear in the 25 November 2010 edition of the journal Nature. Grzegorz Pietrzyński introduces this remarkable result: "By using the HARPS instrument on the 3.6-metre telescope at ESO's La Silla Observatory in Chile, along with other telescopes, we have measured the mass of a Cepheid with an accuracy far greater than any earlier estimates. This new result allows us to immediately see which of the two competing theories predicting the masses of Cepheids is correct." Classical Cepheid Variables, usually called just Cepheids, are unstable stars that are larger and much brighter than the Sun [1]. They expand and contract in a regular way, taking anything from a few days to months to complete the cycle. The time taken to brighten and grow fainter again is longer for stars that are more luminous and shorter for the dimmer ones. This remarkably precise relationship makes the study of Cepheids one of the most effective ways to measure the distances to nearby galaxies and from there to map out the scale of the whole Universe [2]. Unfortunately, despite their importance, Cepheids are not fully understood. Predictions of their masses derived from the theory of pulsating stars are 20-30% less than predictions from the theory of the

  11. Variational iteration method for solving coupled-KdV equations

    International Nuclear Information System (INIS)

    Assas, Laila M.B.

    2008-01-01

    In this paper, the He's variational iteration method is applied to solve the non-linear coupled-KdV equations. This method is based on the use of Lagrange multipliers for identification of optimal value of a parameter in a functional. This technique provides a sequence of functions which converge to the exact solution of the coupled-KdV equations. This procedure is a powerful tool for solving coupled-KdV equations

  12. Multistage Spectral Relaxation Method for Solving the Hyperchaotic Complex Systems

    Directory of Open Access Journals (Sweden)

    Hassan Saberi Nik

    2014-01-01

    Full Text Available We present a pseudospectral method application for solving the hyperchaotic complex systems. The proposed method, called the multistage spectral relaxation method (MSRM is based on a technique of extending Gauss-Seidel type relaxation ideas to systems of nonlinear differential equations and using the Chebyshev pseudospectral methods to solve the resulting system on a sequence of multiple intervals. In this new application, the MSRM is used to solve famous hyperchaotic complex systems such as hyperchaotic complex Lorenz system and the complex permanent magnet synchronous motor. We compare this approach to the Runge-Kutta based ode45 solver to show that the MSRM gives accurate results.

  13. Aging and skilled problem solving.

    Science.gov (United States)

    Charness, N

    1981-03-01

    Information-processing models of problem solving too often are based on restrictive age ranges. On the other hand, gerontologists have investigated few problem-solving tasks and have rarely generated explicit models. As this article demonstrates, both fields can benefit by closer collaboration. One major issue in gerontology is whether aging is associated with irreversible decrement or developmental plasticity. If both processes occur, then an appropriate strategy for investigating aging is to equate age groups for molar problem-solving performance and search for differences in the underlying components. This strategy was adopted to examine the relation of age and skill to problem solving in chess. Chess players were selected to vary widely in age and skill such that these variables were uncorrelated. Problem-solving and memory tasks were administered. Skill level was the only significant predictor for accuracy in both a choose-a-move task and a speeded end-game evaluation task. Age (negatively) and skill (positively) jointly determined performance in an unexpected recall task. Efficient chunking in recall was positively related to skill, though negatively related to age. Recognition confidence, though not accuracy, was negatively related to age. Thus despite age-related declines in encoding and retrieval of information, older players match the problem-solving performance of equivalently skilled younger players. Apparently, they can search the problem space more efficiently, as evidenced by taking less time to select an equally good move. Models of chess skill that stress that role of encoding efficiency, as indexed by chunking in recall, need to be modified to account for performance over the life span.

  14. Simon on Problem-Solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    as a general approach to problem solving. We apply these Simonian ideas to organizational issues, specifically new organizational forms. Specifically, Simonian ideas allow us to develop a morphology of new organizational forms and to point to some design problems that characterize these forms.Keywords: Herbert...... Simon, problem-solving, new organizational forms. JEL Code: D23, D83......Two of Herbert Simon's best-known papers are "The Architecture of Complexity" and "The Structure of Ill-Structured Problems." We discuss the neglected links between these two papers, highlighting the role of decomposition in the context of problems on which constraints have been imposed...

  15. Interactive problem solving using LOGO

    CERN Document Server

    Boecker, Heinz-Dieter; Fischer, Gerhard

    2014-01-01

    This book is unique in that its stress is not on the mastery of a programming language, but on the importance and value of interactive problem solving. The authors focus on several specific interest worlds: mathematics, computer science, artificial intelligence, linguistics, and games; however, their approach can serve as a model that may be applied easily to other fields as well. Those who are interested in symbolic computing will find that Interactive Problem Solving Using LOGO provides a gentle introduction from which one may move on to other, more advanced computational frameworks or more

  16. Customer-centered problem solving.

    Science.gov (United States)

    Samelson, Q B

    1999-11-01

    If there is no single best way to attract new customers and retain current customers, there is surely an easy way to lose them: fail to solve the problems that arise in nearly every buyer-supplier relationship, or solve them in an unsatisfactory manner. Yet, all too frequently, companies do just that. Either we deny that a problem exists, we exert all our efforts to pin the blame elsewhere, or we "Band-Aid" the problem instead of fixing it, almost guaranteeing that we will face it again and again.

  17. Usefulness of the risk assessment technique in solving transportation problems

    International Nuclear Information System (INIS)

    Johnson, J.F.; Hall, R.J.

    1976-08-01

    The purpose was to develop and use a model to assess the risk associated with the shipment of nuclear and non-nuclear hazardous energy-related materials. The analysis method comprises the steps of describing the system, identifying the release sequence, evaluating the sequence, and calculating and assessing the risk. Plutonium shipment is used as an example. Uses of this method to improve transportation safety are discussed. 12 fig

  18. Comparison of Traditional and Innovative Techniques to Solve Technical Challenges

    Science.gov (United States)

    Perchonok, Michele

    2010-01-01

    Although NASA has an adequate food system for current missions, research is required to accommodate new requirements for future NASA exploration missions. The Inadequate Food System risk reflects the need to develop requirements and technologies that will enable NASA to provide the crew with a safe, nutritious and acceptable food system while effectively balancing appropriate resources such as mass, volume, and crew time in exploratory missions. As we go deeper into space or spend more time on the International Space Station (ISS), there will be requirements for packaged food to be stored for 3 5 years. New food packaging technologies are needed that have adequate oxygen and water barrier properties to maintain the foods' quality over this extended shelf life. NASA has been unsuccessful in identify packaging materials that meet the necessary requirements when using several traditional routes including literature reviews, workshops, and internal shelf life studies on foods packaged in various packaging materials. Small Business Innovative Research grants were used for accelerating food packaging materials research with limited success. In order to accelerate the process, a theoretical challenge was submitted to InnoCentive resulting in a partial award. A similar food packaging challenge was submitted to Yet2.com and several potential commercial packaging material suppliers were identified that, at least partially, met the requirements. Comparisons and results of these challenges will be discussed.

  19. An efficient technique to solve combined economic and emission ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... Economic load dispatch is one of the vital purposes in electrical power system operation, management and planning. Economic dispatch problem is one of the most important problems in electric power system operation. In large scale system, the problem is more complex and difficult to find out optimal ...

  20. Effects of problem-solving technique and anxiety management ...

    African Journals Online (AJOL)

    Gender had no significant effect on treatment outcome, while there were no significant interaction effects of gender and treatment on career indecision. Based on these findings the PST and AMT were recommended for reducing career indecision among adolescents in Nigerian schools. Journal of Psychology in Africa 2004, ...

  1. A new technique for solving the 1-D burgers equation

    Directory of Open Access Journals (Sweden)

    Yang Xiaojun

    2017-01-01

    Full Text Available In this paper, we address a new computational method, which is called the decomposition-Sumudu-like-integral-transform method, to handle the 1-D Burgers equation. The proposed method enables the efficient and accurate.

  2. Solving microwave heating model using Hermite-Pade approximation technique

    International Nuclear Information System (INIS)

    Makinde, O.D.

    2005-11-01

    We employ the Hermite-Pade approximation method to explicitly construct the approximate solution of steady state reaction- diffusion equations with source term that arises in modeling microwave heating in an infinite slab with isothermal walls. In particular, we consider the case where the source term decreases spatially and increases with temperature. The important properties of the temperature fields including bifurcations and thermal criticality are discussed. (author)

  3. An efficient technique to solve combined economic and emission ...

    Indian Academy of Sciences (India)

    Economic load dispatch is one of the vital purposes in electrical power system operation, management and planning. Economic dispatch problem is one of the most important problems in electric power system operation. In large scale system, the problem is more complex and difficult to find out optimal solution because it is ...

  4. An efficient technique to solve combined economic and emission ...

    Indian Academy of Sciences (India)

    Abstract. Economic load dispatch is one of the vital purposes in electrical power system operation, management and planning. Economic dispatch problem is one of the most important problems in electric power system operation. In large scale system, the problem is more complex and difficult to find out optimal solution.

  5. Solved problems in classical electromagnetism

    CERN Document Server

    Franklin, Jerrold

    2018-01-01

    This original Dover publication is the companion to a new edition of the author's Classical Electromagnetism: Second Edition. The latter volume will feature only basic answers; this book will contain some problems from the reissue as well as many other new ones. All feature complete, worked-out solutions and form a valuable source of problem-solving material for students.

  6. Quantitative Reasoning in Problem Solving

    Science.gov (United States)

    Ramful, Ajay; Ho, Siew Yin

    2015-01-01

    In this article, Ajay Ramful and Siew Yin Ho explain the meaning of quantitative reasoning, describing how it is used in the to solve mathematical problems. They also describe a diagrammatic approach to represent relationships among quantities and provide examples of problems and their solutions.

  7. Interactive Problem-Solving Interventions

    African Journals Online (AJOL)

    Frew Demeke Alemu

    various interactive problem solving methods. Track III Diplomacy refers to “people to people” search for common ground undertaken by individuals or private groups. This type of activity may involve organizing meetings and conferences, generating media exposure, and political and legal advocacy. 15 Wehrenfennig, Id., p.

  8. Solving Differential Equations in R: Package deSolve

    Directory of Open Access Journals (Sweden)

    Karline Soetaert

    2010-02-01

    Full Text Available In this paper we present the R package deSolve to solve initial value problems (IVP written as ordinary differential equations (ODE, differential algebraic equations (DAE of index 0 or 1 and partial differential equations (PDE, the latter solved using the method of lines approach. The differential equations can be represented in R code or as compiled code. In the latter case, R is used as a tool to trigger the integration and post-process the results, which facilitates model development and application, whilst the compiled code significantly increases simulation speed. The methods implemented are efficient, robust, and well documented public-domain Fortran routines. They include four integrators from the ODEPACK package (LSODE, LSODES, LSODA, LSODAR, DVODE and DASPK2.0. In addition, a suite of Runge-Kutta integrators and special-purpose solvers to efficiently integrate 1-, 2- and 3-dimensional partial differential equations are available. The routines solve both stiff and non-stiff systems, and include many options, e.g., to deal in an efficient way with the sparsity of the Jacobian matrix, or finding the root of equations. In this article, our objectives are threefold: (1 to demonstrate the potential of using R for dynamic modeling, (2 to highlight typical uses of the different methods implemented and (3 to compare the performance of models specified in R code and in compiled code for a number of test cases. These comparisons demonstrate that, if the use of loops is avoided, R code can efficiently integrate problems comprising several thousands of state variables. Nevertheless, the same problem may be solved from 2 to more than 50 times faster by using compiled code compared to an implementation using only R code. Still, amongst the benefits of R are a more flexible and interactive implementation, better readability of the code, and access to R’s high-level procedures. deSolve is the successor of package odesolve which will be deprecated in

  9. Problem-solving phase transitions during team collaboration

    DEFF Research Database (Denmark)

    Wiltshire, Travis; Butner, Jonathan E.; Fiore, Stephen M.

    2018-01-01

    Multiple theories of problem-solving hypothesize that there are distinct qualitative phases exhibited during effective problem-solving. However, limited research has attempted to identify when transitions between phases occur. We integrate theory on collaborative problem-solving (CPS) with dynami......Multiple theories of problem-solving hypothesize that there are distinct qualitative phases exhibited during effective problem-solving. However, limited research has attempted to identify when transitions between phases occur. We integrate theory on collaborative problem-solving (CPS......) with dynamical systems theory suggesting that when a system is undergoing a phase transition it should exhibit a peak in entropy and that entropy levels should also relate to team performance. Communications from 40 teams that collaborated on a complex problem were coded for occurrence of problem......-solving processes. We applied a sliding window entropy technique to each team's communications and specified criteria for (a) identifying data points that qualify as peaks and (b) determining which peaks were robust. We used multilevel modeling, and provide a qualitative example, to evaluate whether phases exhibit...

  10. Planning under uncertainty solving large-scale stochastic linear programs

    Energy Technology Data Exchange (ETDEWEB)

    Infanger, G. [Stanford Univ., CA (United States). Dept. of Operations Research]|[Technische Univ., Vienna (Austria). Inst. fuer Energiewirtschaft

    1992-12-01

    For many practical problems, solutions obtained from deterministic models are unsatisfactory because they fail to hedge against certain contingencies that may occur in the future. Stochastic models address this shortcoming, but up to recently seemed to be intractable due to their size. Recent advances both in solution algorithms and in computer technology now allow us to solve important and general classes of practical stochastic problems. We show how large-scale stochastic linear programs can be efficiently solved by combining classical decomposition and Monte Carlo (importance) sampling techniques. We discuss the methodology for solving two-stage stochastic linear programs with recourse, present numerical results of large problems with numerous stochastic parameters, show how to efficiently implement the methodology on a parallel multi-computer and derive the theory for solving a general class of multi-stage problems with dependency of the stochastic parameters within a stage and between different stages.

  11. Computer techniques for electromagnetics

    CERN Document Server

    Mittra, R

    1973-01-01

    Computer Techniques for Electromagnetics discusses the ways in which computer techniques solve practical problems in electromagnetics. It discusses the impact of the emergence of high-speed computers in the study of electromagnetics. This text provides a brief background on the approaches used by mathematical analysts in solving integral equations. It also demonstrates how to use computer techniques in computing current distribution, radar scattering, and waveguide discontinuities, and inverse scattering. This book will be useful for students looking for a comprehensive text on computer techni

  12. Assessing Algebraic Solving Ability: A Theoretical Framework

    Science.gov (United States)

    Lian, Lim Hooi; Yew, Wun Thiam

    2012-01-01

    Algebraic solving ability had been discussed by many educators and researchers. There exists no definite definition for algebraic solving ability as it can be viewed from different perspectives. In this paper, the nature of algebraic solving ability in terms of algebraic processes that demonstrate the ability in solving algebraic problem is…

  13. Assertiveness and problem solving in midwives

    Directory of Open Access Journals (Sweden)

    Zeliha Burcu Yurtsal

    2015-01-01

    Conclusions: There were significant statistical differences between assertiveness levels and problem solving skills of midwives, and midwives who were assertive solved their problems better than did others. Assertiveness and problem-solving skills training will contribute to the success of the midwifery profession. Midwives able to solve problems, and display assertive behaviors will contribute to the development of midwifery profession.

  14. An NOy* Algorithm for SOLVE

    Science.gov (United States)

    Loewenstein, M.; Greenblatt. B. J.; Jost, H.; Podolske, J. R.; Elkins, Jim; Hurst, Dale; Romanashkin, Pavel; Atlas, Elliott; Schauffler, Sue; Donnelly, Steve; hide

    2000-01-01

    De-nitrification and excess re-nitrification was widely observed by ER-2 instruments in the Arctic vortex during SOLVE in winter/spring 2000. Analyses of these events requires a knowledge of the initial or pre-vortex state of the sampled air masses. The canonical relationship of NOy to the long-lived tracer N2O observed in the unperturbed stratosphere is generally used for this purpose. In this paper we will attempt to establish the current unperturbed NOy:N2O relationship (NOy* algorithm) using the ensemble of extra-vortex data from in situ instruments flying on the ER-2 and DC-8, and from the Mark IV remote measurements on the OMS balloon. Initial analysis indicates a change in the SOLVE NOy* from the values predicted by the 1994 Northern Hemisphere NOy* algorithm which was derived from the observations in the ASHOE/MAESA campaign.

  15. The Teacher as a Role Model in Problem Solving

    Science.gov (United States)

    Cherkas, Barry M.

    1978-01-01

    The author discusses the use of free-hand drawing, the modified Socratic teaching method, and the differentiation of mathematical language from colloquial usage as techniques which he has found helpful in creating a positive classroom environment for teaching problem solving. (MN)

  16. Objective Oriented Problem Solving a Case Study: Mugher Cement ...

    African Journals Online (AJOL)

    Abstract. Objective Oriented Problem Solving technique is presented in two stages, namely the analysis phase and the planning phase. The first deals with the analysis of participants, problems, objectives and alternatives. In the second phase an explanation on how to form a planning matrix is given by way of discussing ...

  17. Undergraduate Performance in Solving Ill-Defined Biochemistry Problems

    Science.gov (United States)

    Sensibaugh, Cheryl A.; Madrid, Nathaniel J.; Choi, Hye-Jeong; Anderson, William L.; Osgood, Marcy P.

    2017-01-01

    With growing interest in promoting skills related to the scientific process, we studied performance in solving ill-defined problems demonstrated by graduating biochemistry majors at a public, minority-serving university. As adoption of techniques for facilitating the attainment of higher-order learning objectives broadens, so too does the need to…

  18. Some Implicit Methods for Solving Harmonic Variational Inequalities

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam Noor

    2016-08-01

    Full Text Available In this paper, we use the auxiliary principle technique to suggest an implicit method for solving the harmonic variational inequalities. It is shown that the convergence of the proposed method only needs pseudo monotonicity of the operator, which is a weaker condition than monotonicity.

  19. A genetic algorithm selection perturbative hyper-heuristic for solving ...

    African Journals Online (AJOL)

    Hyper-heuristics, on the other hand, search a heuristic space with the aim of providing a more generalized solution to the particular optimisation problem. This is a fairly new technique that has proven to be successful in solving various combinatorial optimisation problems. There has not been much research into the use of ...

  20. SolveDB: Integrating Optimization Problem Solvers Into SQL Databases

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Pedersen, Torben Bach

    2016-01-01

    for optimization problems, (2) an extensible infrastructure for integrating different solvers, and (3) query optimization techniques to achieve the best execution performance and/or result quality. Extensive experiments with the PostgreSQL-based implementation show that SolveDB is a versatile tool offering much...

  1. Simulated annealing approach for solving economic load dispatch ...

    African Journals Online (AJOL)

    user

    Abstract. This paper presents Simulated Annealing (SA) algorithm for optimization inspired by the process of annealing in ... Various classical optimization techniques were used to solve the ELD problem, for example: lambda iteration approach, ...... Research of fuzzy self-adaptive immune algorithm and its application.

  2. Graphical representation of the process of solving problems in statics

    Science.gov (United States)

    Lopez, Carlos

    2011-03-01

    It is presented a method of construction to a graphical representation technique of knowledge called Conceptual Chains. Especially, this tool has been focused to the representation of processes and applied to solving problems in physics, mathematics and engineering. The method is described in ten steps and is illustrated with its development in a particular topic of statics. Various possible didactic applications of this technique are showed.

  3. University Physics As a Second Language: Mastering Problem Solving

    Science.gov (United States)

    Barrett, Tom

    2005-09-01

    Get a better grade in Physics Solving physics problems can be challenging at times. But with hard work and the right study tools, you can learn the language of physics and get the grade you want. With Tom Barrett's University Physics as a Second Language(TM): Mastering Problem Solving, you'll be able to better understand fundamental physics concepts, solve a variety of problems, and focus on what you need to know to succeed. Here's how you can get a better grade in physics: Understand the basic concepts University Physics as a Second Language(TM) focuses on selected topics in calculus-based physics to give you a solid foundation. Tom Barrett explains these topics in clear, easy-to-understand language. Break problems down into simple steps University Physics as a Second Language(TM) teaches you to approach problems more efficiently and effectively. You'll learn how to recognize common patterns in physics problems, break problems down into manageable steps, and apply appropriate techniques. The book takes you step-by-step through the solutions to numerous examples. Improve your problem-solving skills University Physics as a Second Language(TM) will help you develop the skills you need to solve a variety of problem types. You'll learn timesaving problem-solving strategies that will help you focus your efforts, as well as how to avoid potential pitfalls.

  4. Problem solving through recreational mathematics

    CERN Document Server

    Averbach, Bonnie

    1999-01-01

    Historically, many of the most important mathematical concepts arose from problems that were recreational in origin. This book takes advantage of that fact, using recreational mathematics - problems, puzzles and games - to teach students how to think critically. Encouraging active participation rather than just observation, the book focuses less on mathematical results than on how these results can be applied to thinking about problems and solving them. Each chapter contains a diverse array of problems in such areas as logic, number and graph theory, two-player games of strategy, solitaire ga

  5. Scaffolding for solving problem in static fluid: A case study

    Science.gov (United States)

    Koes-H, Supriyono; Muhardjito, Wijaya, Charisma P.

    2018-01-01

    Problem solving is one of the basic abilities that should be developed from learning physics. However, students still face difficulties in the process of non-routine problem-solving. Efforts are necessary to be taken in order to identify such difficulties and the solutions to solve them. An effort in the form of a diagnosis of students' performance in problem solving can be taken to identify their difficulties, and various instructional scaffolding supports can be utilized to eliminate the difficulties. This case study aimed to describe the students' difficulties in solving static fluid problems and the effort to overcome such difficulties through different scaffolding supports. The research subjects consisted of four 10-grade students of (Public Senior High School) SMAN 4 Malang selected by purposive sampling technique. The data of students' difficulties were collected via think-aloud protocol implemented on students' performance in solving non-routine static fluid problems. Subsequently, combined scaffolding supports were given to the students based on their particular difficulties. The research findings pointed out that there were several conceptual difficulties discovered from the students when solving static fluid problems, i.e. the use of buoyancy force formula, determination of all forces acting on a plane in a fluid, the resultant force on a plane in a fluid, and determination of a plane depth in a fluid. An effort that can be taken to overcome such conceptual difficulties is providing a combination of some appropriate scaffolding supports, namely question prompts with specific domains, simulation, and parallel modeling. The combination can solve students' lack of knowledge and improve their conceptual understanding, as well as help them to find solutions by linking the problems with their prior knowledge. According to the findings, teachers are suggested to diagnose the students' difficulties so that they can provide an appropriate combination of

  6. L'impact des développements scientifiques sur la résolution des problèmes techniques posés par la nouvelle conjoncture dans l'exploration et la production du pétrole Impact of Scientific Developments on the Solving of Technical Problems Raised by the New Economic Situation in Oil Exploration and Production

    Directory of Open Access Journals (Sweden)

    Tissot B.

    2006-11-01

    Full Text Available Dans les circonstances difficiles que traverse l'exploration et la production du pétrole, le savoir-faire technologique, associé à la maîtrise des coûts, seront pour l'industrie pétrolière et parapétrolière des atouts essentiels. On envisage ici l'impact prévisible des développements scientifiques sur la résolution des problèmes techniques dans l'exploration et la production. Les principales disciplines scientifiques concernées (géologie, géophysique, géochimie, mécanique des roches et des sols, mécanique des fluides, physicochimie des interfaces ainsi que trois techniques de base (modélisation, systèmes experts, matériaux nouveaux sont examinées dans ce sens. En particulier,la modélisation numérique voit son importance croître de manière spectaculaire : elle couvre désormais des domaines nouveaux, comme les Sciences de la Terre, et continue à s'enrichir de développements importants, même dans les secteurs où on l'utilise depuis 20 ans comme la production. Ces évolutions s'accompagneront nécessairement d'ajustements dans la formation des hommes et le fonctionnement des organisations; en particulier un espace nouveau pourrait se dégager pour de petites entreprises de conseil et de service plus riches en matière grise qu'en investissements lourds. In the difficult circumstances now confronting oil exploration and production, technical know-how combined with cost control will be essential assets for the petroleum and petroleum equipment and service industries. This article considers the foreseeable impact of scientific developments on the solving of technical problems in exploration and production. The principal scientific disciplines involved (geology, geophysics, geochemistry, rock and soil mechanics, fluid mechanics, interface physicochemistry as well as three basic techniques (modeling, expert systems, new materials are examined within this context. In particular, numerical modeling is increasing in

  7. Multiparameter extrapolation and deflation methods for solving equation systems

    Directory of Open Access Journals (Sweden)

    A. J. Hughes Hallett

    1984-01-01

    Full Text Available Most models in economics and the applied sciences are solved by first order iterative techniques, usually those based on the Gauss-Seidel algorithm. This paper examines the convergence of multiparameter extrapolations (accelerations of first order iterations, as an improved approximation to the Newton method for solving arbitrary nonlinear equation systems. It generalises my earlier results on single parameter extrapolations. Richardson's generalised method and the deflation method for detecting successive solutions in nonlinear equation systems are also presented as multiparameter extrapolations of first order iterations. New convergence results are obtained for those methods.

  8. Solving traveling salesman problems with DNA molecules encoding numerical values.

    Science.gov (United States)

    Lee, Ji Youn; Shin, Soo-Yong; Park, Tai Hyun; Zhang, Byoung-Tak

    2004-12-01

    We introduce a DNA encoding method to represent numerical values and a biased molecular algorithm based on the thermodynamic properties of DNA. DNA strands are designed to encode real values by variation of their melting temperatures. The thermodynamic properties of DNA are used for effective local search of optimal solutions using biochemical techniques, such as denaturation temperature gradient polymerase chain reaction and temperature gradient gel electrophoresis. The proposed method was successfully applied to the traveling salesman problem, an instance of optimization problems on weighted graphs. This work extends the capability of DNA computing to solving numerical optimization problems, which is contrasted with other DNA computing methods focusing on logical problem solving.

  9. A Cognitive Analysis of Students’ Mathematical Problem Solving Ability on Geometry

    Science.gov (United States)

    Rusyda, N. A.; Kusnandi, K.; Suhendra, S.

    2017-09-01

    The purpose of this research is to analyze of mathematical problem solving ability of students in one of secondary school on geometry. This research was conducted by using quantitative approach with descriptive method. Population in this research was all students of that school and the sample was twenty five students that was chosen by purposive sampling technique. Data of mathematical problem solving were collected through essay test. The results showed the percentage of achievement of mathematical problem solving indicators of students were: 1) solve closed mathematical problems with context in math was 50%; 2) solve the closed mathematical problems with the context beyond mathematics was 24%; 3) solving open mathematical problems with contexts in mathematics was 35%; And 4) solving open mathematical problems with contexts outside mathematics was 44%. Based on the percentage, it can be concluded that the level of achievement of mathematical problem solving ability in geometry still low. This is because students are not used to solving problems that measure mathematical problem solving ability, weaknesses remember previous knowledge, and lack of problem solving framework. So the students’ ability of mathematical problems solving need to be improved with implement appropriate learning strategy.

  10. Solving rational expectations models using Excel

    DEFF Research Database (Denmark)

    Strulik, Holger

    2004-01-01

    Problems of discrete time optimal control can be solved using backward iteration and Microsoft Excel. The author explains the method in general and shows how the basic models of neoclassical growth and real business cycles are solved......Problems of discrete time optimal control can be solved using backward iteration and Microsoft Excel. The author explains the method in general and shows how the basic models of neoclassical growth and real business cycles are solved...

  11. Effects of practicing creative problem solving

    OpenAIRE

    Bojanović, Radojica; Đurišić-Bojanović, Mirosava

    2016-01-01

    This paper tests the effect of practicing creative problem solving in the context of business. The research was conducted on a sample of final-year students (N=90). Participants were solving the initial and final test of creative problem solving in the context of business, as well as the creativity test. Practicing creative problem solving lasted around four monts (around 40 minutes a week). Practice method combined a nominal method of group decision making and Osborn creativity method. The b...

  12. Combinatorial techniques

    CERN Document Server

    Sane, Sharad S

    2013-01-01

    This is a basic text on combinatorics that deals with all the three aspects of the discipline: tricks, techniques and theory, and attempts to blend them. The book has several distinctive features. Probability and random variables with their interconnections to permutations are discussed. The theme of parity has been specially included and it covers applications ranging from solving the Nim game to the quadratic reciprocity law. Chapters related to geometry include triangulations and Sperner's theorem, classification of regular polytopes, tilings and an introduction to the Eulcidean Ramsey theory. Material on group actions covers Sylow theory, automorphism groups and a classification of finite subgroups of orthogonal groups. All chapters have a large number of exercises with varying degrees of difficulty, ranging from material suitable for Mathematical Olympiads to research.

  13. Scaffolding the Development of Problem-Solving Skills in Chemistry: Guiding Novice Students out of Dead Ends and False Starts

    Science.gov (United States)

    Yuriev, Elizabeth; Naidu, Som; Schembri, Luke S.; Short, Jennifer L.

    2017-01-01

    To scaffold the development of problem-solving skills in chemistry, chemistry educators are exploring a variety of instructional techniques. In this study, we have designed, implemented, and evaluated a problem-solving workflow--''Goldilocks Help''. This workflow builds on work done in the field of problem solving in chemistry and provides…

  14. Decision e Informacion en Solucion de Problemas. Publicacion No. 77 (Information and Decision Making in Problem Solving. Publication No. 77).

    Science.gov (United States)

    Rimoldi, Horacio J. A.; And Others

    A technique using information and decision-making theories to evaluate problem solving tactics is presented. In problem solving, the process of solution is evaluated by investigating the questions that the subject doing the problem solving asks. The sequence of questions asked is called a tactic. It is assumed that: (1) tactics are the observable…

  15. LEGO Robotics: An Authentic Problem Solving Tool?

    Science.gov (United States)

    Castledine, Alanah-Rei; Chalmers, Chris

    2011-01-01

    With the current curriculum focus on correlating classroom problem solving lessons to real-world contexts, are LEGO robotics an effective problem solving tool? This present study was designed to investigate this question and to ascertain what problem solving strategies primary students engaged with when working with LEGO robotics and whether the…

  16. A recursive centered T-matrix algorithm to solve the multiple scattering equation: numerical validation

    CERN Document Server

    Auger, J C

    2003-01-01

    The multiple scattering problem can be solved using various analytical techniques. One of these techniques, the T-matrix formalism, is at the present time generally solved using iterative algorithms, because the initially proposed recursive algorithms appeared to be numerically unstable. We present here a new set of recursive relations to solve the multiple scattering equation, and discuss their range of application. In order to validate this new formalism, we compare numerical results for various complex systems with the Generalized Multi-particle Mie solution. We show that the results obtained with the recursive method are in very good agreement with those given by iterative techniques.

  17. Solving the structure of metakaolin

    Energy Technology Data Exchange (ETDEWEB)

    Proffen, Thomas E [Los Alamos National Laboratory; White, Claire E [Los Alamos National Laboratory; Provis, John L [UNIV. OF MELBOURNE; Riley, Daniel P [UNIV. OF MELBOURNE; Van Deventer, Jannie S J [UNIV. OF MELBOURNE

    2009-01-01

    Metakaolin has been used extensively as a cement additive and paint extender, and recently as a geopolymer precursor. This disordered layered aluminosilicate is formed via the dehydroxylation of kaolinite. However, an accurate representation of its atomic structure has bever before been presented. Here, a novel synergy between total scattering and density functional modeling is presented to solve the structure of metakaolin. The metastable structure is elucidated by iterating between least-squares real-space refinement using neutron pair distribution function data, and geometry optimization using density functional modeling. The resulting structural representation is both energetically feasible and in excellent agreement with experimental data. This accurate structure of metakaolin provides new insight into the local environment of the aluminum atoms, with evidence of the existence of tri-coordinated aluminum. By the availability of this detailed atomic description, there exists the opportunity to tailor chemical and mechanical processes involving metakaolin at the atomic level to obtain optimal performance at the macro-scale.

  18. Solving Rectangular Fuzzy Games through

    Directory of Open Access Journals (Sweden)

    Chaudhuri Arindam

    2017-12-01

    Full Text Available Fuzzy set theory has been applied in many fields such as operations research, control theory and decision sciences. In particular, an application of this theory in decision making problems has a remarkable significance. In this paper, we consider a solution of rectangular fuzzy game with pay-off as imprecise numbers instead of crisp numbers viz., interval and LR-type trapezoidal fuzzy numbers. The solution of such fuzzy games with pure strategies by minimax-maximin principle is discussed. The algebraic method to solve 2 × 2 fuzzy games without saddle point by using mixed strategies is also illustrated. Here m × n payoff matrix is reduced to 2 × 2 pay-off matrix by dominance method. This fact is illustrated by means of numerical example.

  19. Adaptive Problem Solving by Analogy

    Science.gov (United States)

    2013-07-01

    gestalt   psychologist  developed  a  number of  rules which prescribe when  and how  visual   features  are be bound  together.  There is however a...tracking,  visualization   of the working memory, and a script language for setting‐up and controlling simulations.  Summary and dissemination are presented in...set of  visual   features belong  to  the  same object).  The binding problem  is  also  relevant  to  problem solving as long as prior to finding a

  20. Domain decomposition methods for solving an image problem

    Energy Technology Data Exchange (ETDEWEB)

    Tsui, W.K.; Tong, C.S. [Hong Kong Baptist College (Hong Kong)

    1994-12-31

    The domain decomposition method is a technique to break up a problem so that ensuing sub-problems can be solved on a parallel computer. In order to improve the convergence rate of the capacitance systems, pre-conditioned conjugate gradient methods are commonly used. In the last decade, most of the efficient preconditioners are based on elliptic partial differential equations which are particularly useful for solving elliptic partial differential equations. In this paper, the authors apply the so called covering preconditioner, which is based on the information of the operator under investigation. Therefore, it is good for various kinds of applications, specifically, they shall apply the preconditioned domain decomposition method for solving an image restoration problem. The image restoration problem is to extract an original image which has been degraded by a known convolution process and additive Gaussian noise.

  1. [Methods for teaching problem-solving in medical schools].

    Science.gov (United States)

    Shumway, J M; Vargas, M E; Heller, L E

    1984-01-01

    The need to include in the medical curriculum instructional activities to promote the development of problem-solving abilities has been asserted at the national and international levels. In research on the mental process involved in the solution of problems in medicine, problem-solving has been defined as a hypothetical-deductive activity engaged in by experienced physicians, in which the early generation of hypotheses influences the subsequent gathering of information. This article comments briefly on research on the mental process by which medical problems are solved. It describes the methods that research has shown to be most applicable in instruction to develop problem-solving abilities, and presents some educational principles that justify their application. The "trail-following" approach is the method that has been most commonly used to study the physician's problem-solving behavior. The salient conclusions from this research are that in the problem-solving process the diagnostic hypothesis is generated very early on and with limited data; the number of hypotheses is small; the problem-solving approach is specific to the type of medical problem and case in hand; and the accumulation of medical knowledge and experience forms the basis of clinical competence. Four methods for teaching the solution of problems are described: case presentation, the rain of ideas, the nominal groups technique and decision-making consensus, the census and analysis of forces in the field, and the analysis of clinical decisions. These methods are carried out in small groups. The advantages of the small groups are that the students are active participants in the learning process, they receive formative evaluation of their performance in a setting conductive to learning, and are able to interact with their instructor if he makes proper use of the right questioning techniques. While no single problem-solving method can be useful to all students or in all the problems they encounter

  2. Review on solving the forward problem in EEG source analysis

    Directory of Open Access Journals (Sweden)

    Vergult Anneleen

    2007-11-01

    methods are required to solve these sparse linear systems. The following iterative methods are discussed: successive over-relaxation, conjugate gradients method and algebraic multigrid method. Conclusion Solving the forward problem has been well documented in the past decades. In the past simplified spherical head models are used, whereas nowadays a combination of imaging modalities are used to accurately describe the geometry of the head model. Efforts have been done on realistically describing the shape of the head model, as well as the heterogenity of the tissue types and realistically determining the conductivity. However, the determination and validation of the in vivo conductivity values is still an important topic in this field. In addition, more studies have to be done on the influence of all the parameters of the head model and of the numerical techniques on the solution of the forward problem.

  3. Podejście PDCA Problem Solving w rozwiązywaniu problemów organizacji

    OpenAIRE

    Obora, Hubert

    2010-01-01

    The aim of this paper is to present one of newest team oriented problem solving method – PDCA Problem Solving. The author introduces the origin and essence of the method. He also describes the various stages involved In PDCA Problem Solving and presents examples of auxiliary methods and techniques. The last section of the paper is an attempt at evaluating the application PDCA Problem Solving as a method of continuous improvement.

  4. Peer instruction enhanced meaningful learning: ability to solve novel problems.

    Science.gov (United States)

    Cortright, Ronald N; Collins, Heidi L; DiCarlo, Stephen E

    2005-06-01

    Students must be able to interpret, relate, and incorporate new information with existing knowledge and apply the new information to solve novel problems. Peer instruction is a cooperative learning technique that promotes critical thinking, problem solving, and decision-making skills. Therefore, we tested the hypothesis that peer instruction enhances meaningful learning or transfer, defined as the student's ability to solve novel problems or the ability to extend what has been learned in one context to new contexts. To test this hypothesis, our undergraduate exercise physiology class of 38 students was randomly divided into two groups: group A (n = 19) and group B (n = 19). A randomized crossover design in which students either answered questions individually or during peer instruction was used to control for time and order effects. The first factor that influences meaningful learning is the degree of mastery of the original material. Importantly, peer instruction significantly enhanced mastery of the original material. Furthermore, the student's ability to solve novel problems was significantly enhanced following peer instruction. Thus pausing two to three times during a 50-min class to allow peer instruction enhanced the mastery of the original material and enhanced meaningful learning, i.e., the student's ability to solve novel problems.

  5. Solving Fractional Programming Problems based on Swarm Intelligence

    Science.gov (United States)

    Raouf, Osama Abdel; Hezam, Ibrahim M.

    2014-04-01

    This paper presents a new approach to solve Fractional Programming Problems (FPPs) based on two different Swarm Intelligence (SI) algorithms. The two algorithms are: Particle Swarm Optimization, and Firefly Algorithm. The two algorithms are tested using several FPP benchmark examples and two selected industrial applications. The test aims to prove the capability of the SI algorithms to solve any type of FPPs. The solution results employing the SI algorithms are compared with a number of exact and metaheuristic solution methods used for handling FPPs. Swarm Intelligence can be denoted as an effective technique for solving linear or nonlinear, non-differentiable fractional objective functions. Problems with an optimal solution at a finite point and an unbounded constraint set, can be solved using the proposed approach. Numerical examples are given to show the feasibility, effectiveness, and robustness of the proposed algorithm. The results obtained using the two SI algorithms revealed the superiority of the proposed technique among others in computational time. A better accuracy was remarkably observed in the solution results of the industrial application problems.

  6. Community-powered problem solving.

    Science.gov (United States)

    Gouillart, Francis; Billings, Douglas

    2013-04-01

    Traditionally, companies have managed their constituencies with specific processes: marketing to customers, procuring from vendors, developing HR policies for employees, and so on. The problem is, such processes focus on repeatability and compliance, so they can lead to stagnation. Inviting your constituencies to collectively help you solve problems and exploit opportunities--"co-creation"--is a better approach. It allows you to continually tap the skills and insights of huge numbers of stakeholders and develop new ways to produce value for all. The idea is to provide stakeholders with platforms (physical and digital forums) on which they can interact, get them to start exploring new experiences and connections, and let the system grow organically. A co-creation initiative by a unit of Becton, Dickinson and Company demonstrates how this works. A global leader in syringes, BD set out to deepen its ties with hospital customers and help them reduce the incidence of infections from unsafe injection and syringe disposal practices. The effort began with a cross-functional internal team, brought in the hospital procurement and supply managers BD had relationships with, and then reached out to hospitals' infection-prevention and occupational health leaders. Eventually product designers, nurses, sustainability staffers, and even hospital CFOs were using the platform, contributing data that generated new best practices and reduced infections.

  7. Students’ difficulties in probabilistic problem-solving

    Science.gov (United States)

    Arum, D. P.; Kusmayadi, T. A.; Pramudya, I.

    2018-03-01

    There are many errors can be identified when students solving mathematics problems, particularly in solving the probabilistic problem. This present study aims to investigate students’ difficulties in solving the probabilistic problem. It focuses on analyzing and describing students errors during solving the problem. This research used the qualitative method with case study strategy. The subjects in this research involve ten students of 9th grade that were selected by purposive sampling. Data in this research involve students’ probabilistic problem-solving result and recorded interview regarding students’ difficulties in solving the problem. Those data were analyzed descriptively using Miles and Huberman steps. The results show that students have difficulties in solving the probabilistic problem and can be divided into three categories. First difficulties relate to students’ difficulties in understanding the probabilistic problem. Second, students’ difficulties in choosing and using appropriate strategies for solving the problem. Third, students’ difficulties with the computational process in solving the problem. Based on the result seems that students still have difficulties in solving the probabilistic problem. It means that students have not able to use their knowledge and ability for responding probabilistic problem yet. Therefore, it is important for mathematics teachers to plan probabilistic learning which could optimize students probabilistic thinking ability.

  8. Modelling, screening, and solving of optimisation problems: Application to industrial metal forming processes

    NARCIS (Netherlands)

    Bonte, M.H.A.; van den Boogaard, Antonius H.; Veldman, E.

    2007-01-01

    Coupling Finite Element (FEM) simulations to mathematical optimisation techniques provides a high potential to improve industrial metal forming processes. In order to optimise these processes, all kind of optimisation problems need to be mathematically modelled and subsequently solved using an

  9. Algorithms Design Techniques and Analysis

    CERN Document Server

    Alsuwaiyel, M H

    1999-01-01

    Problem solving is an essential part of every scientific discipline. It has two components: (1) problem identification and formulation, and (2) solution of the formulated problem. One can solve a problem on its own using ad hoc techniques or follow those techniques that have produced efficient solutions to similar problems. This requires the understanding of various algorithm design techniques, how and when to use them to formulate solutions and the context appropriate for each of them. This book advocates the study of algorithm design techniques by presenting most of the useful algorithm desi

  10. Constructing the Lyapunov Function through Solving Positive Dimensional Polynomial System

    Directory of Open Access Journals (Sweden)

    Zhenyi Ji

    2013-01-01

    Full Text Available We propose an approach for constructing Lyapunov function in quadratic form of a differential system. First, positive polynomial system is obtained via the local property of the Lyapunov function as well as its derivative. Then, the positive polynomial system is converted into an equation system by adding some variables. Finally, numerical technique is applied to solve the equation system. Some experiments show the efficiency of our new algorithm.

  11. Solving Bus Terminal Location Problem Using Genetic Algorithm

    OpenAIRE

    S. Babaie-Kafaki; R. Ghanbari; S.H. Nasseri; E. Ardil

    2008-01-01

    Bus networks design is an important problem in public transportation. The main step to this design, is determining the number of required terminals and their locations. This is an especial type of facility location problem, a large scale combinatorial optimization problem that requires a long time to be solved. The genetic algorithm (GA) is a search and optimization technique which works based on evolutionary principle of natural chromosomes. Specifically, the evolution o...

  12. Monte Carlo method for solving a parabolic problem

    Directory of Open Access Journals (Sweden)

    Tian Yi

    2016-01-01

    Full Text Available In this paper, we present a numerical method based on random sampling for a parabolic problem. This method combines use of the Crank-Nicolson method and Monte Carlo method. In the numerical algorithm, we first discretize governing equations by Crank-Nicolson method, and obtain a large sparse system of linear algebraic equations, then use Monte Carlo method to solve the linear algebraic equations. To illustrate the usefulness of this technique, we apply it to some test problems.

  13. Variational Iteration Method for Solving a Fuzzy Generalized Pantograph Equation

    Directory of Open Access Journals (Sweden)

    A. Amiri

    2014-05-01

    Full Text Available A numerical method for solving the fuzzy generalized pantograph equation under fuzzy initial value conditions is presented. This technique provides a sequence of functions which converges to the exact solution to the problem and is based on the use of Lagrange multipliers for identification of optimal value of a parameter in a functional. To display the validity and applicability of the numerical method two illustrative examples are presented.

  14. Teaching effective problem solving skills to radiation protection students

    International Nuclear Information System (INIS)

    Waller, Edward

    2008-01-01

    Full text: Problem solving skills are essential for all radiation protection personnel. Although some students have more natural problem solving skills than others, all students require practice to become comfortable using these skills. At the University of Ontario Institute of Technology (UOIT), a unique one-semester course was developed as part of the core curriculum to teach students problem solving skills and elements of modelling and simulation. The underlying emphasis of the course was to allow students to develop their own problem solving strategies, both individually and in groups. Direction was provided on how to examine problems from different perspectives, and how to determine the proper root problem statement. A five-point problem solving strategy was presented as: 1) Problem definition; 2) Solution generation; 3) Decision; 4) Implementation; 5) Evaluation. Within the strategy, problem solving techniques were integrated from diverse areas such as: De Bono 's six thinking hats, Kepner-Tregoe decision analysis, Covey's seven habits of highly effective people, Reason's swiss cheese theory of complex failure, and Howlett's common failure modes. As part of the evaluation step, students critically explore areas such as ethics and environmental responsibility. In addition to exploring problem solving methods, students learn the usefulness of simulation methods, and how to model and simulate complex phenomena of relevance to radiation protection. Computational aspects of problem solving are explored using the commercially available MATLAB computer code. A number of case studies are presented as both examples and problems to the students. Emphasis was placed on solutions to problems of interest to radiation protection, health physics and nuclear engineering. A group project, pertaining to an accident or event related to the nuclear industry is a course requirement. Students learn to utilize common time and project management tools such as flowcharting, Pareto

  15. Conceptual problem solving in high school physics

    OpenAIRE

    Jennifer L. Docktor; Natalie E. Strand; José P. Mestre; Brian H. Ross

    2015-01-01

    Problem solving is a critical element of learning physics. However, traditional instruction often emphasizes the quantitative aspects of problem solving such as equations and mathematical procedures rather than qualitative analysis for selecting appropriate concepts and principles. This study describes the development and evaluation of an instructional approach called Conceptual Problem Solving (CPS) which guides students to identify principles, justify their use, and plan their solution in w...

  16. Solving graph problems with dynamic computation structures

    Science.gov (United States)

    Babb, Jonathan W.; Frank, Matthew; Agarwal, Anant

    1996-10-01

    We introduce dynamic computation structures (DCS), a compilation technique to produce dynamic code for reconfigurable computing. DCS specializes directed graph instances into user-level hardware for reconfigurable architectures. Several problems such as shortest path and transitive closure exhibit the general properties of closed semirings, an algebraic structure for solving directed paths. Motivating our application domain choice of closed semiring problems is the fact that logic emulation software already maps a special case of directed graphs, namely logic netlists, onto arrays of field programmable gate arrays (FPGA). A certain type of logic emulation software called virtual wires further allows an FPGA array to be viewed as a machine-independent computing fabric. Thus, a virtual wires compiler, coupled with front-end commercial behavioral logic synthesis software, enables automatic behavioral compilation into a multi-FPGA computing fabric. We have implemented a DCS front-end compiler to parallelize the entire inner loop of the classic Bellman-Ford algorithm into synthesizable behavioral verilog. Leveraging virtual wire compilation and behavioral synthesis, we have automatically generated designs of 14 to 261 FPGAs from a single graph instance. We achieve speedups proportional to the number of graph edges - - from 10X to almost 400X versus a 125 SPECint SparcStation 10.

  17. Projective geometry solved problems and theory review

    CERN Document Server

    Fortuna, Elisabetta; Pardini, Rita

    2016-01-01

    This book starts with a concise but rigorous overview of the basic notions of projective geometry, using straightforward and modern language. The goal is not only to establish the notation and terminology used, but also to offer the reader a quick survey of the subject matter. In the second part, the book presents more than 200 solved problems, for many of which several alternative solutions are provided. The level of difficulty of the exercises varies considerably: they range from computations to harder problems of a more theoretical nature, up to some actual complements of the theory. The structure of the text allows the reader to use the solutions of the exercises both to master the basic notions and techniques and to further their knowledge of the subject, thus learning some classical results not covered in the first part of the book. The book addresses the needs of undergraduate and graduate students in the theoretical and applied sciences, and will especially benefit those readers with a solid grasp of ...

  18. An Integrated Architecture for Engineering Problem Solving

    National Research Council Canada - National Science Library

    Pisan, Yusuf

    1998-01-01

    .... This thesis describes the Integrated Problem Solving Architecture (IPSA) that combines qualitative, quantitative and diagrammatic reasoning skills to produce annotated solutions to engineering problems...

  19. Mobile serious games for collaborative problem solving.

    Science.gov (United States)

    Sanchez, Jaime; Mendoza, Claudia; Salinas, Alvaro

    2009-01-01

    This paper presents the results obtained from the implementation of a series of learning activities based on mobile serious games (MSG) for the development of problem-solving and collaborative skills in Chilean 8th grade students. Three MSGs were developed and played by teams of four students, who had to solve the problems posed by the game collaboratively. The data shows that the experimental group had a higher perception of their own skills of collaboration and of the plan execution dimension of problem solving than the control group, providing empirical evidence regarding the contribution of MSGs to the development of collaborative problem-solving skills.

  20. Distance Measurement Solves Astrophysical Mysteries

    Science.gov (United States)

    2003-08-01

    Location, location, and location. The old real-estate adage about what's really important proved applicable to astrophysics as astronomers used the sharp radio "vision" of the National Science Foundation's Very Long Baseline Array (VLBA) to pinpoint the distance to a pulsar. Their accurate distance measurement then resolved a dispute over the pulsar's birthplace, allowed the astronomers to determine the size of its neutron star and possibly solve a mystery about cosmic rays. "Getting an accurate distance to this pulsar gave us a real bonanza," said Walter Brisken, of the National Radio Astronomy Observatory (NRAO) in Socorro, NM. Monogem Ring The Monogem Ring, in X-Ray Image by ROSAT satellite CREDIT: Max-Planck Institute, American Astronomical Society (Click on Image for Larger Version) The pulsar, called PSR B0656+14, is in the constellation Gemini, and appears to be near the center of a circular supernova remnant that straddles Gemini and its neighboring constellation, Monoceros, and is thus called the Monogem Ring. Since pulsars are superdense, spinning neutron stars left over when a massive star explodes as a supernova, it was logical to assume that the Monogem Ring, the shell of debris from a supernova explosion, was the remnant of the blast that created the pulsar. However, astronomers using indirect methods of determining the distance to the pulsar had concluded that it was nearly 2500 light-years from Earth. On the other hand, the supernova remnant was determined to be only about 1000 light-years from Earth. It seemed unlikely that the two were related, but instead appeared nearby in the sky purely by a chance juxtaposition. Brisken and his colleagues used the VLBA to make precise measurements of the sky position of PSR B0656+14 from 2000 to 2002. They were able to detect the slight offset in the object's apparent position when viewed from opposite sides of Earth's orbit around the Sun. This effect, called parallax, provides a direct measurement of

  1. Solving Cubic Equations by Polynomial Decomposition

    Science.gov (United States)

    Kulkarni, Raghavendra G.

    2011-01-01

    Several mathematicians struggled to solve cubic equations, and in 1515 Scipione del Ferro reportedly solved the cubic while participating in a local mathematical contest, but did not bother to publish his method. Then it was Cardano (1539) who first published the solution to the general cubic equation in his book "The Great Art, or, The Rules of…

  2. Problem Solving Methods in Engineering Design

    DEFF Research Database (Denmark)

    Hartvig, Susanne C

    1999-01-01

    This short paper discusses typical engineering tasks and problem solving methods, based on a field study of engineering tasks at a Danish engineering firm. The field study has identified ten classes of design tasks and in this paper these classes are related to problem solving methods...

  3. Creativity and Insight in Problem Solving

    Science.gov (United States)

    Golnabi, Laura

    2016-01-01

    This paper analyzes the thought process involved in problem solving and its categorization as creative thinking as defined by psychologist R. Weisberg (2006). Additionally, the notion of insight, sometimes present in unconscious creative thinking and often leading to creative ideas, is discussed in the context of geometry problem solving. In…

  4. Teaching Problem Solving: An Instructional Design Strategy.

    Science.gov (United States)

    Ross, John A.; Maynes, Florence J.

    1983-01-01

    Instructional design strategy for improving problem solving is presented. The strategy entails selecting an appropriate domain of problem-solving tasks, learning hierarchies, teaching methods and assembling of learning materials, and designing teacher training and evaluation. Obstacles to be overcome and directions for future research are…

  5. Teaching Problem-Solving. Informal Series/43.

    Science.gov (United States)

    Ross, John A.; Maynes, Florence J.

    This monograph is designed to provide practical classroom suggestions, including sample lesson plans, to show how teachers can improve the problem-solving competence of students at all educational and ability levels. The examples provided show that problem-solving instruction can be integrated with teaching the content of particular topics. While…

  6. Mathematical problem solving in primary school

    NARCIS (Netherlands)

    Kolovou, A.

    2011-01-01

    A student is engaged in (non-routine) problem solving when there is no clear pathway to the solution. In contrast to routine problems, non-routine ones cannot be solved through the direct application of a standard procedure. Consider the following problem: In a quiz you get two points for each

  7. Conceptual Problem Solving in High School Physics

    Science.gov (United States)

    Docktor, Jennifer L.; Strand, Natalie E.; Mestre, José P.; Ross, Brian H.

    2015-01-01

    Problem solving is a critical element of learning physics. However, traditional instruction often emphasizes the quantitative aspects of problem solving such as equations and mathematical procedures rather than qualitative analysis for selecting appropriate concepts and principles. This study describes the development and evaluation of an…

  8. Solving applied mathematical problems with Matlab

    CERN Document Server

    Xue, Dingyu

    2008-01-01

    Computer Mathematics Language-An Overview. Fundamentals of MATLAB Programming. Calculus Problems. MATLAB Computations of Linear Algebra Problems. Integral Transforms and Complex Variable Functions. Solutions to Nonlinear Equations and Optimization Problems. MATLAB Solutions to Differential Equation Problems. Solving Interpolations and Approximations Problems. Solving Probability and Mathematical Statistics Problems. Nontraditional Solution Methods for Mathematical Problems.

  9. Measuring Problem Solving Skills in "Portal 2"

    Science.gov (United States)

    Shute, Valerie J.; Wang, Lubin

    2013-01-01

    This paper examines possible improvement to problem solving skills as a function of playing the video game "Portal 2." Stealth assessment is used in the game to evaluate students' problem solving abilities--specifically basic and flexible rule application. The stealth assessment measures will be validated against commonly accepted…

  10. Concept mapping instrumental support for problem solving

    NARCIS (Netherlands)

    Stoyanov, S.; Stoyanov, Slavi; Kommers, Petrus A.M.

    2008-01-01

    The main theoretical position of this paper is that it is the explicit problem-solving support in concept mapping software that produces a stronger effect in problem-solving performance than the implicit support afforded by the graphical functionality of concept mapping software. Explicit

  11. Students’ Algebraic Reasonsing In Solving Mathematical Problems With Adversity Quotient

    Science.gov (United States)

    Aryani, F.; Amin, S. M.; Sulaiman, R.

    2018-01-01

    Algebraic reasoning is a process in which students generalize mathematical ideas from a set of particular instances and express them in increasingly formal and age-appropriate ways. Using problem solving approach to develop algebraic reasoning of mathematics may enhace the long-term learning trajectory of the majority students. The purpose of this research was to describe the algebraic reasoning of quitter, camper, and climber junior high school students in solving mathematical problems. This research used qualitative descriptive method. Subjects were determined by purposive sampling. The technique of collecting data was done by task-based interviews.The results showed that the algebraic reasoning of three students in the process of pattern seeking by identifying the things that are known and asked in a similar way. But three students found the elements of pattern recognition in different ways or method. So, they are generalize the problem of pattern formation with different ways. The study of algebraic reasoning and problem solving can be a learning paradigm in the improve students’ knowledge and skills in algebra work. The goal is to help students’ improve academic competence, develop algebraic reasoning in problem solving.

  12. Synthesizing Huber's Problem Solving and Kolb's Learning Cycle: A Balanced Approach to Technical Problem Solving

    Science.gov (United States)

    Kamis, Arnold; Khan, Beverly K.

    2009-01-01

    How do we model and improve technical problem solving, such as network subnetting? This paper reports an experimental study that tested several hypotheses derived from Kolb's experiential learning cycle and Huber's problem solving model. As subjects solved a network subnetting problem, they mapped their mental processes according to Huber's…

  13. System to solve three designs of the fuel management

    International Nuclear Information System (INIS)

    Castillo M, J. A.; Ortiz S, J. J.; Montes T, J. L.; Perusquia del C, R.; Marinez R, R.

    2015-09-01

    In this paper preliminary results are presented, obtained with the development of a computer system that resolves three stages of the nuclear fuel management, which are: the axial and radial designs of fuel, as well as the design of nuclear fuel reloads. The novelty of the system is that the solution is obtained solving the 3 mentioned stages, in coupled form. For this, heuristic techniques are used for each stage, in each one of these has a function objective that is applied to particular problems, but in all cases the obtained partial results are used as input data for the next stage. The heuristic techniques that were used to solve the coupled problem are: tabu search, neural networks and a hybrid between the scatter search and path re linking. The system applies an iterative process from the design of a fuel cell to the reload design, since are preliminary results the reload is designed using the operation strategy Haling type. In each one of the stages nuclear parameters inherent to the design are monitored. The results so far show the advantage of solving the problem in a coupled manner, even when a large amount of computer resources is used. (Author)

  14. Lesion mapping of social problem solving

    Science.gov (United States)

    Colom, Roberto; Paul, Erick J.; Chau, Aileen; Solomon, Jeffrey; Grafman, Jordan H.

    2014-01-01

    Accumulating neuroscience evidence indicates that human intelligence is supported by a distributed network of frontal and parietal regions that enable complex, goal-directed behaviour. However, the contributions of this network to social aspects of intellectual function remain to be well characterized. Here, we report a human lesion study (n = 144) that investigates the neural bases of social problem solving (measured by the Everyday Problem Solving Inventory) and examine the degree to which individual differences in performance are predicted by a broad spectrum of psychological variables, including psychometric intelligence (measured by the Wechsler Adult Intelligence Scale), emotional intelligence (measured by the Mayer, Salovey, Caruso Emotional Intelligence Test), and personality traits (measured by the Neuroticism-Extraversion-Openness Personality Inventory). Scores for each variable were obtained, followed by voxel-based lesion–symptom mapping. Stepwise regression analyses revealed that working memory, processing speed, and emotional intelligence predict individual differences in everyday problem solving. A targeted analysis of specific everyday problem solving domains (involving friends, home management, consumerism, work, information management, and family) revealed psychological variables that selectively contribute to each. Lesion mapping results indicated that social problem solving, psychometric intelligence, and emotional intelligence are supported by a shared network of frontal, temporal, and parietal regions, including white matter association tracts that bind these areas into a coordinated system. The results support an integrative framework for understanding social intelligence and make specific recommendations for the application of the Everyday Problem Solving Inventory to the study of social problem solving in health and disease. PMID:25070511

  15. Problem-solving competency of nursing graduates.

    Science.gov (United States)

    Uys, Leana R; Van Rhyn, Lily L; Gwele, Nomthandaso S; McInerney, Patricia; Tanga, Tobeka

    2004-12-01

    This paper reports a study describing and evaluating the outcomes of problem-based learning (PBL) programmes in nursing schools in South Africa in terms of the competence of graduates to solve problem in actual clinical settings, and comparing this competence with that of graduates from non-PBL programmes. The nursing literature tends to equate problem-solving with patient-centred problems or the nursing process. However, it is also a skill used in managing the work role, working in a team and managing a health care unit. Problem-solving refers to the process of selectively attending to information in a patient care setting. The investigation of problem-solving in nursing is complicated by the complex relationships between different cognitive processes. A qualitative evaluation study, descriptive and comparative in nature, was carried out. In-depth interviews were held with graduates and their supervisors, asking them to identify problem-solving incidents in which they had been involved. Template analysis style and Benner's interpretive approach were used to analyse the data. The majority of the incidents described by the graduates (84%) were graded at the advanced beginner level or above. The majority of incidents at the novice level came from the non-PBL group. 'Using people skills' and 'being assertive' were the two problem-solving strategies most often used. The PBL group fared better than the non-problem-based group in the level of their problem-solving ability. The findings of this study suggest that further research is warranted into the problem-solving abilities of PBL graduates, their personal development over time and at different stages of practice. In addition, it would be interesting to follow the development of their problem-solving abilities over time.

  16. The ideal science student and problem solving

    Science.gov (United States)

    Sullivan, Florence R.

    2005-09-01

    The purpose of this dissertation was to examine the relationship between students' social mental models of the ideal science student, science epistemological beliefs, problem solving strategies used, and problem solving ability in a robotics environment. Participants were twenty-six academically advanced eleven and twelve year old students attending the Center for Talented Youth summer camp. Survey data was collected from the students including demographic background, views of the ideal science student, and science epistemological beliefs. Students also solved a robotics challenge. This problem solving session was videotaped and students were asked to think aloud as they solved the problem. Two social mental models were identified, a traits-based social mental model and a robust social mental model. A significant association was found between social mental model group and strategy usage. The robust social mental model group is more likely to use domain specific strategies than the traits-based group. Additionally, the robust social mental model group achieved significantly higher scores on their final solution than the traits-based social mental model group. Science epistemological beliefs do not appear to be associated with students' social mental model of the ideal science student. While students with a puzzle-solver view of science were more likely to use domain specific strategies in the planning phase of the problem solving session, there was no significant difference in problem solving ability between this group and students who have a dynamic view of the nature of science knowledge. This difference in strategy usage and problem solving performance may be due to a difference in the students' views of learning and cognition. The robust social mental model group evidenced a situative view of learning and cognition. These students made excellent use of the tools available in the task environment. The traits-based social mental model group displayed an

  17. Assertiveness and problem solving in midwives.

    Science.gov (United States)

    Yurtsal, Zeliha Burcu; Özdemir, Levent

    2015-01-01

    Midwifery profession is required to bring solutions to problems and a midwife is expected to be an assertive person and to develop midwifery care. This study was planned to examine the relationship between assertiveness and problem-solving skills of midwives. This cross-sectional study was conducted with 201 midwives between July 2008 and February 2009 in the city center of Sivas. The Rathus Assertiveness Schedule (RAS) and Problem Solving Inventory (PSI) were used to determine the level of assertiveness and problem-solving skills of midwives. Statistical methods were used as mean, standard deviation, percentage, Student's T, ANOVA and Tukey HSD, Kruskal Wallis, Fisher Exact, Pearson Correlation and Chi-square tests and P < 0.05. The RAS mean scores and the PSI mean scores showed statistically significant differences in terms of a midwife's considering herself as a member of the health team, expressing herself within the health care team, being able to say "no" when necessary, cooperating with her colleagues, taking part in problem-solving skills training. A statistically significant negative correlation was found between the RAS and PSI scores. The RAS scores decreased while the problem-solving scores increased (r: -0451, P < 0.01). There were significant statistical differences between assertiveness levels and problem solving skills of midwives, and midwives who were assertive solved their problems better than did others. Assertiveness and problem-solving skills training will contribute to the success of the midwifery profession. Midwives able to solve problems, and display assertive behaviors will contribute to the development of midwifery profession.

  18. Comparison of problem solving tools in lean organizations

    Directory of Open Access Journals (Sweden)

    Iuga Maria Virginia

    2017-01-01

    Full Text Available As global market competition is getting fiercer, and companies are looking at ways to stay on top, more and more organizations are looking at Lean Manufacturing and lean tools to support them in achieving their goals. Especially within the automotive industry, lean practices are very well received. The speed at which the automotive industry is evolving, especially but not only, in countries like Romania, leads to the need to carefully analyze lean manufacturing concepts, examine them against local production conditions, and to develop and standardize them. One of the most important things to take into consideration here is the application of an adequate problem solving technique to avoid waste. The objective of this research paper lies in analyzing and comparing the problem-solving methods recommended by the Toyota Production System, and to propose their appropriate application at shop floor, in relation to the specific problem type.

  19. Improving mathematical problem solving : A computerized approach

    NARCIS (Netherlands)

    Harskamp, EG; Suhre, CJM

    Mathematics teachers often experience difficulties in teaching students to become skilled problem solvers. This paper evaluates the effectiveness of two interactive computer programs for high school mathematics problem solving. Both programs present students with problems accompanied by instruction

  20. Exact Algorithms for Solving Stochastic Games

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Koucky, Michal; Lauritzen, Niels

    2012-01-01

    Shapley's discounted stochastic games, Everett's recursive games and Gillette's undiscounted stochastic games are classical models of game theory describing two-player zero-sum games of potentially infinite duration. We describe algorithms for exactly solving these games....

  1. How to solve applied mathematics problems

    CERN Document Server

    Moiseiwitsch, B L

    2011-01-01

    This workbook bridges the gap between lectures and practical applications, offering students of mathematics, engineering, and physics the chance to practice solving problems from a wide variety of fields. 2011 edition.

  2. Deterministic equation solving over finite fields

    NARCIS (Netherlands)

    Woestijne, Christiaan Evert van de

    2006-01-01

    It is shown how to solve diagonal forms in many variables over finite fields by means of a deterministic efficient algorithm. Applications to norm equations, quadratic forms, and elliptic curves are given.

  3. Physics: Quantum problems solved through games

    Science.gov (United States)

    Maniscalco, Sabrina

    2016-04-01

    Humans are better than computers at performing certain tasks because of their intuition and superior visual processing. Video games are now being used to channel these abilities to solve problems in quantum physics. See Letter p.210

  4. Thinking about Applications: Effects on Mental Models and Creative Problem-Solving

    Science.gov (United States)

    Barrett, Jamie D.; Peterson, David R.; Hester, Kimberly S.; Robledo, Issac C.; Day, Eric A.; Hougen, Dean P.; Mumford, Michael D.

    2013-01-01

    Many techniques have been used to train creative problem-solving skills. Although the available techniques have often proven to be effective, creative training often discounts the value of thinking about applications. In this study, 248 undergraduates were asked to develop advertising campaigns for a new high-energy soft drink. Solutions to this…

  5. The art and science of problem solving

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2005-01-01

    In this paper we will document that real-life problem solving in complex situations demands both rational (scientific) and intuitive (artistic) thinking. First, the concepts of art and science will be discussed; differences and similarities will be enhanced. Thereafter the concept of group problem...... solving facilitation both as science and art will be presented. A case study related to examination's planning will be discussed to illustrate the main concepts in practice. In addition, other cases studies will also be shortly presented....

  6. Methods for solving mathematical physics problems

    CERN Document Server

    Agoshkov, VI; Shutyaev, VP

    2006-01-01

    The book examines the classic and generally accepted methods for solving mathematical physics problems (method of the potential theory, the eigenfunction method, integral transformation methods, discretisation characterisation methods, splitting methods). A separate chapter is devoted to methods for solving nonlinear equations. The book offers a large number of examples of how these methods are applied to the solution of specific mathematical physics problems, applied in the areas of science and social activities, such as energy, environmental protection, hydrodynamics, theory of elasticity, etc.

  7. Conceptual problem solving in high school physics

    Directory of Open Access Journals (Sweden)

    Jennifer L. Docktor

    2015-09-01

    Full Text Available Problem solving is a critical element of learning physics. However, traditional instruction often emphasizes the quantitative aspects of problem solving such as equations and mathematical procedures rather than qualitative analysis for selecting appropriate concepts and principles. This study describes the development and evaluation of an instructional approach called Conceptual Problem Solving (CPS which guides students to identify principles, justify their use, and plan their solution in writing before solving a problem. The CPS approach was implemented by high school physics teachers at three schools for major theorems and conservation laws in mechanics and CPS-taught classes were compared to control classes taught using traditional problem solving methods. Information about the teachers’ implementation of the approach was gathered from classroom observations and interviews, and the effectiveness of the approach was evaluated from a series of written assessments. Results indicated that teachers found CPS easy to integrate into their curricula, students engaged in classroom discussions and produced problem solutions of a higher quality than before, and students scored higher on conceptual and problem solving measures.

  8. Conceptual problem solving in high school physics

    Science.gov (United States)

    Docktor, Jennifer L.; Strand, Natalie E.; Mestre, José P.; Ross, Brian H.

    2015-12-01

    Problem solving is a critical element of learning physics. However, traditional instruction often emphasizes the quantitative aspects of problem solving such as equations and mathematical procedures rather than qualitative analysis for selecting appropriate concepts and principles. This study describes the development and evaluation of an instructional approach called Conceptual Problem Solving (CPS) which guides students to identify principles, justify their use, and plan their solution in writing before solving a problem. The CPS approach was implemented by high school physics teachers at three schools for major theorems and conservation laws in mechanics and CPS-taught classes were compared to control classes taught using traditional problem solving methods. Information about the teachers' implementation of the approach was gathered from classroom observations and interviews, and the effectiveness of the approach was evaluated from a series of written assessments. Results indicated that teachers found CPS easy to integrate into their curricula, students engaged in classroom discussions and produced problem solutions of a higher quality than before, and students scored higher on conceptual and problem solving measures.

  9. A Model for Solving the Maxwell Quasi Stationary Equations in a 3-Phase Electric Reduction Furnace

    Directory of Open Access Journals (Sweden)

    S. Ekrann

    1982-10-01

    Full Text Available A computer code has been developed for the approximate computation of electric and magnetic fields within an electric reduction furnace. The paper describes the numerical methods used to solve Maxwell's quasi-stationary equations, which are the governing equations for this problem. The equations are discretized by a staggered grid finite difference technique. The resulting algebraic equations are solved by iterating between computations of electric and magnetic quantities. This 'outer' iteration converges only when the skin depth is larger or of about the same magnitude as the linear dimensions of the computational domain. In solving for electric quantities with magnetic quantities being regarded as known, and vice versa, the central computational task is the solution of a Poisson equation for a scalar potential. These equations are solved by line successive overrelaxation combined with a rebalancing technique.

  10. The effect of learning environments based on problem solving on students’ achievements of problem solving

    Directory of Open Access Journals (Sweden)

    Ilhan Karatas

    2013-07-01

    Full Text Available Problem solving is recognized as an important life skill involving a range of processes including analyzing, interpreting, reasoning, predicting, evaluating and reflecting. For that reason educating students as efficient problem solvers is an important role of mathematics education. Problem solving skill is the centre of mathematics curriculum. Students’ gaining of that skill in school mathematics is closely related with the learning environment to be formed and the roles given to the students. The aim of this study is to create a problem solving based learning environment to enhance the students’ problem solving skill. Within this scope, students’ practiced activities and problems that provide them to proceed in Polya (1945’s problem solving phases and throughout the study, students’ success in problem solving have been evaluated. While experimental group students received problem solving based learning environment performed, control group students have continued their present program in this quise-experimental study. Eleven problem solving activities were given to the students at the beginning, middle and end of the study and the students’ performances were analyzed based on problem solving phases. The findings illustrated that the experimental group students’ success in problem solving activities has increased while the control group students’ success has not changed significantly.

  11. The Effect of Learning Environments Based on Problem Solving on Students’ Achievements of Problem Solving

    Directory of Open Access Journals (Sweden)

    Ilhan KARATAS

    2013-07-01

    Full Text Available Problem solving is recognized as an important life skill involving a range of processes including analyzing, interpreting, reasoning, predicting, evaluating and reflecting. For that reason educatingstudents as efficient problem solvers is an important role of mathematics education. Problem solving skill is the centre of mathematics curriculum. Students’ gaining of that skill in school mathematics is closely related with the learning environment to beformed and the roles given to the students. The aim of this study is to create a problem solving based learning environment to enhance the students’ problem solving skill. Within this scope, students’practiced activities and problems that provide them to proceed in Polya (1945’s problem solving phases and throughout the study, students’ success in problem solving have been evaluated. While experimental group students received problem solving based learning environment performed, control group students have continued their present program in this quise1experimental study. Eleven problem solving activities were given to the students at the beginning, middle and end of the study and the students’ performances wereanalyzed based on problem solving phases. The findings illustrated that the experimental group students’ success in problem solving activities has increased while the control group students’ success has not changed significantly.

  12. Development of a problem solving evaluation instrument; untangling of specific problem solving assets

    Science.gov (United States)

    Adams, Wendy Kristine

    The purpose of my research was to produce a problem solving evaluation tool for physics. To do this it was necessary to gain a thorough understanding of how students solve problems. Although physics educators highly value problem solving and have put extensive effort into understanding successful problem solving, there is currently no efficient way to evaluate problem solving skill. Attempts have been made in the past; however, knowledge of the principles required to solve the subject problem are so absolutely critical that they completely overshadow any other skills students may use when solving a problem. The work presented here is unique because the evaluation tool removes the requirement that the student already have a grasp of physics concepts. It is also unique because I picked a wide range of people and picked a wide range of tasks for evaluation. This is an important design feature that helps make things emerge more clearly. This dissertation includes an extensive literature review of problem solving in physics, math, education and cognitive science as well as descriptions of studies involving student use of interactive computer simulations, the design and validation of a beliefs about physics survey and finally the design of the problem solving evaluation tool. I have successfully developed and validated a problem solving evaluation tool that identifies 44 separate assets (skills) necessary for solving problems. Rigorous validation studies, including work with an independent interviewer, show these assets identified by this content-free evaluation tool are the same assets that students use to solve problems in mechanics and quantum mechanics. Understanding this set of component assets will help teachers and researchers address problem solving within the classroom.

  13. An improved spectral homotopy analysis method for solving boundary layer problems

    Directory of Open Access Journals (Sweden)

    Sibanda Precious

    2011-01-01

    Full Text Available Abstract This article presents an improved spectral-homotopy analysis method (ISHAM for solving nonlinear differential equations. The implementation of this new technique is shown by solving the Falkner-Skan and magnetohydrodynamic boundary layer problems. The results obtained are compared to numerical solutions in the literature and MATLAB's bvp4c solver. The results show that the ISHAM converges faster and gives accurate results.

  14. The convergence study of the homotopy analysis method for solving nonlinear Volterra-Fredholm integrodifferential equations.

    Science.gov (United States)

    Ghanbari, Behzad

    2014-01-01

    We aim to study the convergence of the homotopy analysis method (HAM in short) for solving special nonlinear Volterra-Fredholm integrodifferential equations. The sufficient condition for the convergence of the method is briefly addressed. Some illustrative examples are also presented to demonstrate the validity and applicability of the technique. Comparison of the obtained results HAM with exact solution shows that the method is reliable and capable of providing analytic treatment for solving such equations.

  15. The Convergence Study of the Homotopy Analysis Method for Solving Nonlinear Volterra-Fredholm Integrodifferential Equations

    Directory of Open Access Journals (Sweden)

    Behzad Ghanbari

    2014-01-01

    Full Text Available We aim to study the convergence of the homotopy analysis method (HAM in short for solving special nonlinear Volterra-Fredholm integrodifferential equations. The sufficient condition for the convergence of the method is briefly addressed. Some illustrative examples are also presented to demonstrate the validity and applicability of the technique. Comparison of the obtained results HAM with exact solution shows that the method is reliable and capable of providing analytic treatment for solving such equations.

  16. The Role of Self Efficacy Towards Mathematical Problem Solving Ability in Terms of Positive Thinking Ability

    OpenAIRE

    Rahmawati Yuliyani; Shinta Dwi Handayani; Somawati Somawati

    2017-01-01

    This research aims to know the influence of the role of self efficacy towards solving math problems in terms of positive thinking. The method used was survey methods with quantitative approach and hypothesis testing using path analysis. Large sample as many as 140 students, with sampling the sampling technique used was saturated. The results of hypothesis testing indicate that: 1) there is a significant direct influence on self efficacy against the ability of solving math problems, with the l...

  17. Multivariate Padé Approximation for Solving Nonlinear Partial Differential Equations of Fractional Order

    Directory of Open Access Journals (Sweden)

    Veyis Turut

    2013-01-01

    Full Text Available Two tecHniques were implemented, the Adomian decomposition method (ADM and multivariate Padé approximation (MPA, for solving nonlinear partial differential equations of fractional order. The fractional derivatives are described in Caputo sense. First, the fractional differential equation has been solved and converted to power series by Adomian decomposition method (ADM, then power series solution of fractional differential equation was put into multivariate Padé series. Finally, numerical results were compared and presented in tables and figures.

  18. Solving Minimal Covering Location Problems with Single and Multiple Node Coverage

    Directory of Open Access Journals (Sweden)

    Darko DRAKULIĆ

    2016-12-01

    Full Text Available Location science represents a very attractiveresearch field in combinatorial optimization and it is in expansion in last five decades. The main objective of location problems is determining the best position for facilities in a given set of nodes.Location science includes techniques for modelling problemsand methods for solving them. This paper presents results of solving two types of minimal covering location problems, with single and multiple node coverage, by using CPLEX optimizer and Particle Swarm Optimization method.

  19. A new neural network model for solving random interval linear programming problems.

    Science.gov (United States)

    Arjmandzadeh, Ziba; Safi, Mohammadreza; Nazemi, Alireza

    2017-05-01

    This paper presents a neural network model for solving random interval linear programming problems. The original problem involving random interval variable coefficients is first transformed into an equivalent convex second order cone programming problem. A neural network model is then constructed for solving the obtained convex second order cone problem. Employing Lyapunov function approach, it is also shown that the proposed neural network model is stable in the sense of Lyapunov and it is globally convergent to an exact satisfactory solution of the original problem. Several illustrative examples are solved in support of this technique. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Solving Nonlinear Partial Differential Equations with Maple and Mathematica

    CERN Document Server

    Shingareva, Inna K

    2011-01-01

    The emphasis of the book is given in how to construct different types of solutions (exact, approximate analytical, numerical, graphical) of numerous nonlinear PDEs correctly, easily, and quickly. The reader can learn a wide variety of techniques and solve numerous nonlinear PDEs included and many other differential equations, simplifying and transforming the equations and solutions, arbitrary functions and parameters, presented in the book). Numerous comparisons and relationships between various types of solutions, different methods and approaches are provided, the results obtained in Maple an

  1. The effectiveness of problem-based learning on students’ problem solving ability in vector analysis course

    Science.gov (United States)

    Mushlihuddin, R.; Nurafifah; Irvan

    2018-01-01

    The student’s low ability in mathematics problem solving proved to the less effective of a learning process in the classroom. Effective learning was a learning that affects student’s math skills, one of which is problem-solving abilities. Problem-solving capability consisted of several stages: understanding the problem, planning the settlement, solving the problem as planned, re-examining the procedure and the outcome. The purpose of this research was to know: (1) was there any influence of PBL model in improving ability Problem solving of student math in a subject of vector analysis?; (2) was the PBL model effective in improving students’ mathematical problem-solving skills in vector analysis courses? This research was a quasi-experiment research. The data analysis techniques performed from the test stages of data description, a prerequisite test is the normality test, and hypothesis test using the ANCOVA test and Gain test. The results showed that: (1) there was an influence of PBL model in improving students’ math problem-solving abilities in vector analysis courses; (2) the PBL model was effective in improving students’ problem-solving skills in vector analysis courses with a medium category.

  2. Computational Psychometrics for the Measurement of Collaborative Problem Solving Skills

    Science.gov (United States)

    Polyak, Stephen T.; von Davier, Alina A.; Peterschmidt, Kurt

    2017-01-01

    This paper describes a psychometrically-based approach to the measurement of collaborative problem solving skills, by mining and classifying behavioral data both in real-time and in post-game analyses. The data were collected from a sample of middle school children who interacted with a game-like, online simulation of collaborative problem solving tasks. In this simulation, a user is required to collaborate with a virtual agent to solve a series of tasks within a first-person maze environment. The tasks were developed following the psychometric principles of Evidence Centered Design (ECD) and are aligned with the Holistic Framework developed by ACT. The analyses presented in this paper are an application of an emerging discipline called computational psychometrics which is growing out of traditional psychometrics and incorporates techniques from educational data mining, machine learning and other computer/cognitive science fields. In the real-time analysis, our aim was to start with limited knowledge of skill mastery, and then demonstrate a form of continuous Bayesian evidence tracing that updates sub-skill level probabilities as new conversation flow event evidence is presented. This is performed using Bayes' rule and conversation item conditional probability tables. The items are polytomous and each response option has been tagged with a skill at a performance level. In our post-game analysis, our goal was to discover unique gameplay profiles by performing a cluster analysis of user's sub-skill performance scores based on their patterns of selected dialog responses. PMID:29238314

  3. Computational Psychometrics for the Measurement of Collaborative Problem Solving Skills.

    Science.gov (United States)

    Polyak, Stephen T; von Davier, Alina A; Peterschmidt, Kurt

    2017-01-01

    This paper describes a psychometrically-based approach to the measurement of collaborative problem solving skills, by mining and classifying behavioral data both in real-time and in post-game analyses. The data were collected from a sample of middle school children who interacted with a game-like, online simulation of collaborative problem solving tasks. In this simulation, a user is required to collaborate with a virtual agent to solve a series of tasks within a first-person maze environment. The tasks were developed following the psychometric principles of Evidence Centered Design (ECD) and are aligned with the Holistic Framework developed by ACT. The analyses presented in this paper are an application of an emerging discipline called computational psychometrics which is growing out of traditional psychometrics and incorporates techniques from educational data mining, machine learning and other computer/cognitive science fields. In the real-time analysis, our aim was to start with limited knowledge of skill mastery, and then demonstrate a form of continuous Bayesian evidence tracing that updates sub-skill level probabilities as new conversation flow event evidence is presented. This is performed using Bayes' rule and conversation item conditional probability tables. The items are polytomous and each response option has been tagged with a skill at a performance level. In our post-game analysis, our goal was to discover unique gameplay profiles by performing a cluster analysis of user's sub-skill performance scores based on their patterns of selected dialog responses.

  4. Computational Psychometrics for the Measurement of Collaborative Problem Solving Skills

    Directory of Open Access Journals (Sweden)

    Stephen T. Polyak

    2017-11-01

    Full Text Available This paper describes a psychometrically-based approach to the measurement of collaborative problem solving skills, by mining and classifying behavioral data both in real-time and in post-game analyses. The data were collected from a sample of middle school children who interacted with a game-like, online simulation of collaborative problem solving tasks. In this simulation, a user is required to collaborate with a virtual agent to solve a series of tasks within a first-person maze environment. The tasks were developed following the psychometric principles of Evidence Centered Design (ECD and are aligned with the Holistic Framework developed by ACT. The analyses presented in this paper are an application of an emerging discipline called computational psychometrics which is growing out of traditional psychometrics and incorporates techniques from educational data mining, machine learning and other computer/cognitive science fields. In the real-time analysis, our aim was to start with limited knowledge of skill mastery, and then demonstrate a form of continuous Bayesian evidence tracing that updates sub-skill level probabilities as new conversation flow event evidence is presented. This is performed using Bayes' rule and conversation item conditional probability tables. The items are polytomous and each response option has been tagged with a skill at a performance level. In our post-game analysis, our goal was to discover unique gameplay profiles by performing a cluster analysis of user's sub-skill performance scores based on their patterns of selected dialog responses.

  5. Solving work-related ethical problems.

    Science.gov (United States)

    Laukkanen, Laura; Suhonen, Riitta; Leino-Kilpi, Helena

    2016-12-01

    Nurse managers are responsible for solving work-related ethical problems to promote a positive ethical culture in healthcare organizations. The aim of this study was to describe the activities that nurse managers use to solve work-related ethical problems. The ultimate aim was to enhance the ethical awareness of all nurse managers. The data for this descriptive cross-sectional survey were analyzed through inductive content analysis and quantification. Participants and research context: The data were collected in 2011 using a questionnaire that included an open-ended question and background factors. Participants were nurse managers working in Finnish healthcare organizations (n = 122). Ethical considerations: Permission for the study was given by the Finnish Association of Academic Managers and Experts of Health Sciences. Nurse managers identified a variety of activities they use to solve work-related ethical problems: discussion (30%), cooperation (25%), work organization (17%), intervention (10%), personal values (9%), operational models (4%), statistics and feedback (4%), and personal examples (1%). However, these activities did not follow any common or systematic model. In the future, nurse managers need a more systematic approach to solve ethical problems. It is important to establish new kinds of ethics structures in organizations, such as a common, systematic ethical decision-making model and an ethics club for nurse manager problems, to support nurse managers in solving work-related ethical problems.

  6. Error analysis in solving mathematical problems

    Directory of Open Access Journals (Sweden)

    Geovana Luiza Kliemann

    2017-12-01

    Full Text Available This paper presents a survey carried out within the Centre for Education Programme, in order to assist in improving the quality of the teaching and learning of Mathematics in Primary Education. From the study of the evaluative systems that constitute the scope of the research project, it was found that their focus is solving problems, and from this point, it began the development of several actions with the purpose of assisting the students in the process of solving them. One of these actions objected to analyze the errors presented by students in the 5th year in the interpretation, understanding, and problem-solving. We describe three games developed in six schools, with questions drawn from the “Prova Brasil” performed in previous years, in objective to diagnose the main difficulties presented by the students in solving the problems, besides helping them to verify possibilities to overcome such gaps. To reach the proposed objectives, a qualitative study was carried out in which the researchers were constantly involved during the process. After each meeting, there was an analysis of the responses developed to classify the errors in different categories. It was found that most students attended succeeded in solving the proposed problems, and major errors presented are related to the difficulty of interpretation.

  7. On Teaching Problem Solving in School Mathematics

    Directory of Open Access Journals (Sweden)

    Erkki Pehkonen

    2013-12-01

    Full Text Available The article begins with a brief overview of the situation throughout the world regarding problem solving. The activities of the ProMath group are then described, as the purpose of this international research group is to improve mathematics teaching in school. One mathematics teaching method that seems to be functioning in school is the use of open problems (i.e., problem fields. Next we discuss the objectives of the Finnish curriculum that are connected with problem solving. Some examples and research results are taken from a Finnish–Chilean research project that monitors the development of problem-solving skills in third grade pupils. Finally, some ideas on “teacher change” are put forward. It is not possible to change teachers, but only to provide hints for possible change routes: the teachers themselves should work out the ideas and their implementation.

  8. Naps improve new walkers' locomotor problem solving.

    Science.gov (United States)

    Berger, Sarah E; Scher, Anat

    2017-10-01

    In this first study of the impact of sleep on infants' problem solving of a locomotor task, 28 newly walking infants who were within a week of having given up crawling trained to navigate a shoulder-height tunnel to reach a caregiver waiting at the end. During the transitional window between crawling and walking, infants are reluctant to return to crawling, making this task uniquely challenging. Infants were randomly assigned to either nap or stay awake during a delay between training and a later test session. For the Nap group, efficiency of problem solving improved from training to test, but there was no change for the No Nap group. These findings suggest that for newly walking infants, sleep facilitates learning to solve a novel motor problem. Published by Elsevier Inc.

  9. The use of Galerkin finite-element methods to solve mass-transport equations

    Science.gov (United States)

    Grove, David B.

    1977-01-01

    The partial differential equation that describes the transport and reaction of chemical solutes in porous media was solved using the Galerkin finite-element technique. These finite elements were superimposed over finite-difference cells used to solve the flow equation. Both convection and flow due to hydraulic dispersion were considered. Linear and Hermite cubic approximations (basis functions) provided satisfactory results: however, the linear functions were computationally more efficient for two-dimensional problems. Successive over relaxation (SOR) and iteration techniques using Tchebyschef polynomials were used to solve the sparce matrices generated using the linear and Hermite cubic functions, respectively. Comparisons of the finite-element methods to the finite-difference methods, and to analytical results, indicated that a high degree of accuracy may be obtained using the method outlined. The technique was applied to a field problem involving an aquifer contaminated with chloride, tritium, and strontium-90. (Woodard-USGS)

  10. Vacuum engineering, calculations, formulas, and solved exercises

    CERN Document Server

    Berman, Armand

    1992-01-01

    This book was written with two main objectives in mind-to summarize and organize the vast material of vacuum technology in sets of useful formulas, and to provide a collection of worked out exercises showing how to use these formulas for solving technological problems. It is an ideal reference source for those with little time to devote to a full mathematical treatment of the many problems issued in vacuum practice, but who have a working knowledge of the essentials of vacuum technology, elementary physics, and mathematics. This time saving book employs a problem-solving approach throughout, p

  11. Student Obstacles in Solving Algebraic Thinking Problems

    Science.gov (United States)

    Andini, W.; Suryadi, D.

    2017-09-01

    The aim of this research is to analize the student obstacles on solving algebraic thinking problems in low grades elementary school. This research is a preliminary qualitative research, and involved 66 students of grade 3 elementary school. From the analysis student test results, most of student experience difficulty in solving algebraic thinking problems. The main obstacle is the student’s difficulty in understanding the problem of generalizing the pattern because the students are not accustomed to see the rules that exist in generalize the pattern.

  12. A Novel Approach for Solving Semidefinite Programs

    Directory of Open Access Journals (Sweden)

    Hong-Wei Jiao

    2014-01-01

    Full Text Available A novel linearizing alternating direction augmented Lagrangian approach is proposed for effectively solving semidefinite programs (SDP. For every iteration, by fixing the other variables, the proposed approach alternatively optimizes the dual variables and the dual slack variables; then the primal variables, that is, Lagrange multipliers, are updated. In addition, the proposed approach renews all the variables in closed forms without solving any system of linear equations. Global convergence of the proposed approach is proved under mild conditions, and two numerical problems are given to demonstrate the effectiveness of the presented approach.

  13. Algorithms to solve the Sutherland model

    OpenAIRE

    Langmann, Edwin

    2001-01-01

    We give a self-contained presentation and comparison of two different algorithms to explicitly solve quantum many body models of indistinguishable particles moving on a circle and interacting with two-body potentials of $1/\\sin^2$-type. The first algorithm is due to Sutherland and well-known; the second one is a limiting case of a novel algorithm to solve the elliptic generalization of the Sutherland model. These two algorithms are different in several details. We show that they are equivalen...

  14. Dreams and creative problem-solving.

    Science.gov (United States)

    Barrett, Deirdre

    2017-10-01

    Dreams have produced art, music, novels, films, mathematical proofs, designs for architecture, telescopes, and computers. Dreaming is essentially our brain thinking in another neurophysiologic state-and therefore it is likely to solve some problems on which our waking minds have become stuck. This neurophysiologic state is characterized by high activity in brain areas associated with imagery, so problems requiring vivid visualization are also more likely to get help from dreaming. This article reviews great historical dreams and modern laboratory research to suggest how dreams can aid creativity and problem-solving. © 2017 New York Academy of Sciences.

  15. Solving network design problems via decomposition, aggregation and approximation

    CERN Document Server

    Bärmann, Andreas

    2016-01-01

    Andreas Bärmann develops novel approaches for the solution of network design problems as they arise in various contexts of applied optimization. At the example of an optimal expansion of the German railway network until 2030, the author derives a tailor-made decomposition technique for multi-period network design problems. Next, he develops a general framework for the solution of network design problems via aggregation of the underlying graph structure. This approach is shown to save much computation time as compared to standard techniques. Finally, the author devises a modelling framework for the approximation of the robust counterpart under ellipsoidal uncertainty, an often-studied case in the literature. Each of these three approaches opens up a fascinating branch of research which promises a better theoretical understanding of the problem and an increasing range of solvable application settings at the same time. Contents Decomposition for Multi-Period Network Design Solving Network Design Problems via Ag...

  16. Solving seismological problems using sgraph program: II-waveform modeling

    International Nuclear Information System (INIS)

    Abdelwahed, Mohamed F.

    2012-01-01

    One of the seismological programs to manipulate seismic data is SGRAPH program. It consists of integrated tools to perform advanced seismological techniques. SGRAPH is considered a new system for maintaining and analyze seismic waveform data in a stand-alone Windows-based application that manipulate a wide range of data formats. SGRAPH was described in detail in the first part of this paper. In this part, I discuss the advanced techniques including in the program and its applications in seismology. Because of the numerous tools included in the program, only SGRAPH is sufficient to perform the basic waveform analysis and to solve advanced seismological problems. In the first part of this paper, the application of the source parameters estimation and hypocentral location was given. Here, I discuss SGRAPH waveform modeling tools. This paper exhibits examples of how to apply the SGRAPH tools to perform waveform modeling for estimating the focal mechanism and crustal structure of local earthquakes.

  17. The Effect of Learning Environments Based on Problem Solving on Students' Achievements of Problem Solving

    Science.gov (United States)

    Karatas, Ilhan; Baki, Adnan

    2013-01-01

    Problem solving is recognized as an important life skill involving a range of processes including analyzing, interpreting, reasoning, predicting, evaluating and reflecting. For that reason educating students as efficient problem solvers is an important role of mathematics education. Problem solving skill is the centre of mathematics curriculum.…

  18. Students' Errors in Solving the Permutation and Combination Problems Based on Problem Solving Steps of Polya

    Science.gov (United States)

    Sukoriyanto; Nusantara, Toto; Subanji; Chandra, Tjang Daniel

    2016-01-01

    This article was written based on the results of a study evaluating students' errors in problem solving of permutation and combination in terms of problem solving steps according to Polya. Twenty-five students were asked to do four problems related to permutation and combination. The research results showed that the students still did a mistake in…

  19. Solving the stationary Liouville equation via a boundary element method

    Science.gov (United States)

    Chappell, David J.; Tanner, Gregor

    2013-02-01

    Energy distributions of linear wave fields are, in the high frequency limit, often approximated in terms of flow or transport equations in phase space. Common techniques for solving the flow equations in both time dependent and stationary problems are ray tracing and level set methods. In the context of predicting the vibro-acoustic response of complex engineering structures, related methods such as Statistical Energy Analysis or variants thereof have found widespread applications. We present a new method for solving the transport equations for complex multi-component structures based on a boundary element formulation of the stationary Liouville equation. The method is an improved version of the Dynamical Energy Analysis technique introduced recently by the authors. It interpolates between standard statistical energy analysis and full ray tracing, containing both of these methods as limiting cases. We demonstrate that the method can be used to efficiently deal with complex large scale problems giving good approximations of the energy distribution when compared to exact solutions of the underlying wave equation.

  20. Enhancing decision-making effectiveness in problem-solving teams.

    Science.gov (United States)

    Bazan, S

    1998-01-01

    Active participation by all group members as well as the generation, presentation, and critical evaluation of a wide range of perspectives and alternatives are hallmarks of effective problem-solving teams. Diverse groups with an odd number of participants (five to seven members are generally best) are manageable and provide an adequate range of perspectives and alternatives. Several problems limit the effectiveness of problem-solving teams. Dysfunctional concurrence or "groupthink" occurs when concurrence seeking in cohesive groups overrides the realistic appraisal of alternative courses of action. Managers initially should withhold their own opinions, assign members the role of critical evaluators, and bring in people from outside the initial group to minimize this problem. Domination by a select few is also a problem because it can squelch the presentation of diverse opinions. Brainstorming and nominal group technique can mitigate this problem. In nominal group technique, a manager guides the group through steps involving brainstorming, recording, and voting on the merits of various alternatives before open discussion is allowed. Decision-making dropouts are group members who withdraw from active participation in the group. Managers can reduce this problem by emphasizing the importance of active participation and by monitoring performance.

  1. Experimental techniques; Techniques experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Roussel-Chomaz, P. [GANIL CNRS/IN2P3, CEA/DSM, 14 - Caen (France)

    2007-07-01

    This lecture presents the experimental techniques, developed in the last 10 or 15 years, in order to perform a new class of experiments with exotic nuclei, where the reactions induced by these nuclei allow to get information on their structure. A brief review of the secondary beams production methods will be given, with some examples of facilities in operation or under project. The important developments performed recently on cryogenic targets will be presented. The different detection systems will be reviewed, both the beam detectors before the targets, and the many kind of detectors necessary to detect all outgoing particles after the reaction: magnetic spectrometer for the heavy fragment, detection systems for the target recoil nucleus, {gamma} detectors. Finally, several typical examples of experiments will be detailed, in order to illustrate the use of each detector either alone, or in coincidence with others. (author)

  2. Cooperative learning, problem solving and mediating artifacts ...

    African Journals Online (AJOL)

    The present study deals with the influence of cooperative learning on the ability of students to solve the problems. The study also concerns the introduction of mathematical mediating artifacts as factors which effect the learning of mathematics by students. Experimental research method of pre-test and post-test types was ...

  3. Solving Word Problems: As Easy As PIES!

    Science.gov (United States)

    Heater, Mary Jane; Howard, Lori A.; Linz, Ed

    2012-01-01

    Many students are challenged when tasked to complete a word problem. While they may know the procedural steps to solve an equation, translating a word problem into an appropriate equation and producing a solution may often cause students to become confused or unwilling to try. This article provides a potential solution for teachers by discussing…

  4. Mental Imagery in Creative Problem Solving.

    Science.gov (United States)

    Polland, Mark J.

    In order to investigate the relationship between mental imagery and creative problem solving, a study of 44 separate accounts reporting mental imagery experiences associated with creative discoveries were examined. The data included 29 different scientists, among them Albert Einstein and Stephen Hawking, and 9 artists, musicians, and writers,…

  5. Solving Problems with the Percentage Bar

    Science.gov (United States)

    van Galen, Frans; van Eerde, Dolly

    2013-01-01

    At the end of primary school all children more of less know what a percentage is, but yet they often struggle with percentage problems. This article describes a study in which students of 13 and 14 years old were given a written test with percentage problems and a week later were interviewed about the way they solved some of these problems. In a…

  6. Three-M in Word Problem Solving

    Science.gov (United States)

    Hajra, Sayonita Ghosh; Kofman, Victoria

    2018-01-01

    We describe three activities that help undergraduates (pre-service teachers) to develop scientific vocabulary on measurable attributes and units of measurement. Measurable attributes are important features in understanding a word problem and solving the problem. These activities help students comprehend word problems better by identifying…

  7. Problem solving environment for distributed interactive applications

    NARCIS (Netherlands)

    Rycerz, K.; Bubak, M.; Sloot, P.; Getov, V.; Gorlatch, S.; Bubak, M.; Priol, T.

    2008-01-01

    Interactive Problem Solving Environments (PSEs) offer an integrated approach for constructing and running complex systems, such as distributed simulation systems. To achieve efficient execution of High Level Architecture (HLA)-based distributed interactive simulations on the Grid, we introduce a PSE

  8. The Use of Transformations in Solving Equations

    Science.gov (United States)

    Libeskind, Shlomo

    2010-01-01

    Many workshops and meetings with the US high school mathematics teachers revealed a lack of familiarity with the use of transformations in solving equations and problems related to the roots of polynomials. This note describes two transformational approaches to the derivation of the quadratic formula as well as transformational approaches to…

  9. Neural Network to Solve Concave Games

    OpenAIRE

    Liu, Zixin; Wang, Nengfa

    2014-01-01

    The issue on neural network method to solve concave games is concerned. Combined with variational inequality, Ky Fan inequality, and projection equation, concave games are transformed into a neural network model. On the basis of the Lyapunov stable theory, some stability results are also given. Finally, two classic games’ simulation results are given to illustrate the theoretical results.

  10. Managing Element Interactivity in Equation Solving

    Science.gov (United States)

    Ngu, Bing Hiong; Phan, Huy P.; Yeung, Alexander Seeshing; Chung, Siu Fung

    2018-01-01

    Between two popular teaching methods (i.e., balance method vs. inverse method) for equation solving, the main difference occurs at the operational line (e.g., +2 on both sides vs. -2 becomes +2), whereby it alters the state of the equation and yet maintains its equality. Element interactivity occurs on both sides of the equation in the balance…

  11. Developing Creative Problem Solving in Civil Engineering.

    Science.gov (United States)

    Barker, Dennis

    1986-01-01

    A British polytechnic's civil engineering course emphasizing creative problem solving, begun in the late 1960s, has shown that it is possible to increase students' creative ability in the course of a degree program. Research into the identification of students who will benefit from the approach is continuing. (MSE)

  12. Young Children's Drawings in Problem Solving

    Science.gov (United States)

    Bakar, Kamariah Abu; Way, Jennifer; Bobis, Janette

    2016-01-01

    This paper explores young children's drawings (6 years old) in early number and addition activities in Malaysia. Observation, informal interviews and analysis of drawings revealed two types of drawing, and gave insight into the transitional process required for children to utilise drawings in problem solving. We argue the importance of valuing and…

  13. A method for solving neutron transport equation

    International Nuclear Information System (INIS)

    Dimitrijevic, Z.

    1993-01-01

    The procedure for solving the transport equation by directly integrating for case one-dimensional uniform multigroup medium is shown. The solution is expressed in terms of linear combination of function H n (x,μ), and the coefficient is determined from given conditions. The solution is applied for homogeneous slab of critical thickness. (author)

  14. On Teaching Problem Solving in School Mathematics

    Science.gov (United States)

    Pehkonen, Erkki; Näveri, Liisa; Laine, Anu

    2013-01-01

    The article begins with a brief overview of the situation throughout the world regarding problem solving. The activities of the ProMath group are then described, as the purpose of this international research group is to improve mathematics teaching in school. One mathematics teaching method that seems to be functioning in school is the use of open…

  15. Problem-Solving Test: Tryptophan Operon Mutants

    Science.gov (United States)

    Szeberenyi, Jozsef

    2010-01-01

    This paper presents a problem-solving test that deals with the regulation of the "trp" operon of "Escherichia coli." Two mutants of this operon are described: in mutant A, the operator region of the operon carries a point mutation so that it is unable to carry out its function; mutant B expresses a "trp" repressor protein unable to bind…

  16. A Microgenetic Study of Insightful Problem Solving

    Science.gov (United States)

    Luwel, Koen; Siegler, Robert S.; Verschaffel, Lieven

    2008-01-01

    An eight-session microgenetic study of acquisition of an insightful problem-solving strategy was conducted. A total of 35 second graders who did not use this insightful strategy initially were assigned to two groups that differed in the frequency of problems likely to facilitate discovery and generalization of the strategy. Children in the…

  17. Reinventing the Wheel: Design and Problem Solving

    Science.gov (United States)

    Blasetti, Sean M.

    2010-01-01

    This article describes a design problem that not only takes students through the technological design process, but it also provides them with real-world problem-solving experience as it relates to the manufacturing and engineering fields. It begins with a scenario placing the student as a custom wheel designer for an automotive manufacturing…

  18. Accounting Exams: Problem Solving or Multiple Choice.

    Science.gov (United States)

    Odaiyappa, Ramasamy

    1989-01-01

    The author studied whether students' preferences for a particular exam format were a function of past performances. He reviews the literature and reports on administration of a questionnaire to 90 accounting students. Results indicate that students prefer problem-solving exams to multiple choice, regardless of past performances. (CH)

  19. A tuning machine for cooperative problem solving

    NARCIS (Netherlands)

    Dunin-Keplicz, B; Verbrugge, R

    2004-01-01

    In this paper we aim to formally model individual, social and collective motivational attitudes in teams of agents involved in Cooperative Problem Solving. Particular attention is given to the strongest motivational attitude, collective commitment, which leads to team action. First, building on our

  20. Multimedia Application for Solving a Sudoku Game

    Directory of Open Access Journals (Sweden)

    Alasu Paul Sabrin

    2009-01-01

    Full Text Available This article explains the way in which, with the help of Action Script 3 in combination with Flash, a method of solving Sudoku game was implemented, through searching for the certain numbers and after that trying to guess for the squares where there are two possible numbers.

  1. 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).

  2. Solving Wicked Problems through Action Learning

    Science.gov (United States)

    Crul, Liselore

    2014-01-01

    This account of practice outlines the Oxyme Action Learning Program which was conducted as part of the Management Challenge in my final year of the MSc in Coaching and Behavioral Change at Henley Business School. The central research questions were: (1) how action learning can help to solve wicked problems and (2) what the effect of an action…

  3. Solving Mathematical Problems A Personal Perspective

    CERN Document Server

    Tao, Terence

    2006-01-01

    Authored by a leading name in mathematics, this engaging and clearly presented text leads the reader through the tactics involved in solving mathematical problems at the Mathematical Olympiad level. With numerous exercises and assuming only basic mathematics, this text is ideal for students of 14 years and above in pure mathematics.

  4. Artists Create Puzzles, Scientists Solve Them.

    Science.gov (United States)

    Goldstein, Joseph L

    2017-09-21

    The Spanish artist Diego Velázquez created a puzzle-painting 360 years ago that to this day remains unsolved, but still mystifies and intrigues. Unlike artists who get their thrills by creating puzzles that stimulate the imagination, scientists get their kicks by solving puzzles that advance biomedical research. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Raise the Bar on Problem Solving

    Science.gov (United States)

    Englard, Lisa

    2010-01-01

    In a 1981 diagnostic test, the Ministry of Education in Singapore found its country facing a challenge: Only 46 percent of students in grades 2-4 could solve word problems that were presented without such key words as "altogether" or "left." Yet today, according to results from the Trends in International Mathematics and…

  6. Adaptive wavelet algorithms for solving operator equations

    NARCIS (Netherlands)

    Gantumur, T.

    2006-01-01

    This thesis treats various aspects of adaptive wavelet algorithms for solving operator equations. For a separable Hilbert space H, a linear functional f in H', and a boundedly invertible linear operator A:H->H', we consider the problem of finding u from H satisfying Au=f. Typically A is given by a

  7. Brain dynamics of mathematical problem solving.

    Science.gov (United States)

    Lin, Chun-Ling; Jung, Melody; Wu, Ying Choon; Lin, Chin-Teng; She, Hsiao-Ching

    2012-01-01

    The purpose of this study is to examine brain activities of participants solving mental math problems. The research investigated how problem difficulty affected the subjects' responses and electroencephalogram (EEG) in different brain regions. In general, it was found that solution latencies (SL) to the math problems increased with difficulty. The EEG results showed that across subjects, the right-central beta, left-parietal theta, left-occipital theta and alpha, right-parietal alpha and beta, medial-frontal beta and medial central theta power decreased as task difficulty increased. This study further explored the effects of problem-solving performance on the EEG. Slow solvers exhibited greater frontal theta activities in the right hemisphere, whereas an inverse pattern of hemispheric asymmetry was found in fast solvers. Furthermore, analyses of spatio-temporal brain dynamics during problem solving show progressively stronger alpha- and beta-power suppression and theta-power augmentation as subjects were reaching a solution. These findings provide a better understanding of cortical activities mediating math-based problem solving and knowledge acquisition that can ultimately benefit math learning and education.

  8. Language and mathematical problem solving among bilinguals.

    Science.gov (United States)

    Bernardo, Allan B I

    2002-05-01

    Does using a bilingual's 1st or 2nd language have an effect on problem solving in semantically rich domains like school mathematics? The author conducted a study to determine whether Filipino-English bilingual students' understanding and solving of word problems in arithmetic differed when the problems were in the students' 1st and 2nd languages. Two groups participated-students whose 1st language was Filipino and students whose 1st language was English-and easy and difficult arithmetic problems were used. The author used a recall paradigm to assess how students understood the word problems and coded the solution accuracy to assess problem solving. The results indicated a 1st-language advantage; that is, the students were better able to understand and solve problems in their 1st language, whether the 1st language was English or Filipino. Moreover, the advantage was more marked with the easy problems. The theoretical and practical implications of the results are discussed.

  9. Discovering Steiner Triple Systems through Problem Solving

    Science.gov (United States)

    Sriraman, Bharath

    2004-01-01

    An attempt to implement problem solving as a teacher of ninth grade algebra is described. The problems selected were not general ones, they involved combinations and represented various situations and were more complex which lead to the discovery of Steiner triple systems.

  10. Counterfactual Problem Solving and Situated Cognition

    Directory of Open Access Journals (Sweden)

    Glebkin V.V.,

    2017-08-01

    Full Text Available The paper describes and interprets data of a study on counterfactual problem solving in representatives of modern industrial culture. The study was inspired by similar experiments carried out by A.R. Luria during his expedition to Central Asia. The hypothesis of our study was that representatives of modern industrial culture would solve counterfactual puzzles at a slower rate and with higher numbers of mistakes than similar non-counterfactual tasks. The experiments we conducted supported this hypothesis as well as provided us with some insights as to how to further develop it. For instance, we found no significant differences in time lag in solving counterfactual and ‘realistic’ tasks between the subjects with mathematical and the ones with liberal arts education. As an interpretation of the obtained data, we suggest a two-stage model of counterfactual problem solving: on the first stage, where situated cognition dominates, the realistic situation is transferred into the system of symbols unrelated to this very situation; on the second stage, operations are carried out within the framework of this new system of symbols.

  11. Fuzzy linear programming approach for solving transportation ...

    Indian Academy of Sciences (India)

    ALI EBRAHIMNEJAD

    satisfy demands at destinations using available supplies at origins. Transportation problem can be used for a wide vari- ety of situations such as scheduling, production, investment, plant location, inventory control, employment scheduling and many others. In general, transportation problems are solved with the assumptions ...

  12. Facilitating Problem Solving in High School Chemistry.

    Science.gov (United States)

    Gabel, Dorothy L.; Sherwood, Robert D.

    1983-01-01

    Investigated superiority of instructional strategies (factor-label method, proportionality, use of analogies, use of diagrams) in teaching problem-solving related to mole concept, gas laws, stoichiometry, and molarity. Also investigated effectiveness of strategies for students (N=609) with different verbal-visual preferences, proportional…

  13. Problem Solving. Workplace Strategies for Thoughtful Change.

    Science.gov (United States)

    Diller, Janelle; Moore, Rita

    This learning module is designed to enable participants to look at problems from a variety of perspectives, to apply a basic problem-solving strategy, to implement a plan of action, and to identify problems that are of particular importance to their workplace. The module includes units for six class sessions. Each unit includes the following…

  14. Problem Solving Model for Science Learning

    Science.gov (United States)

    Alberida, H.; Lufri; Festiyed; Barlian, E.

    2018-04-01

    This research aims to develop problem solving model for science learning in junior high school. The learning model was developed using the ADDIE model. An analysis phase includes curriculum analysis, analysis of students of SMP Kota Padang, analysis of SMP science teachers, learning analysis, as well as the literature review. The design phase includes product planning a science-learning problem-solving model, which consists of syntax, reaction principle, social system, support system, instructional impact and support. Implementation of problem-solving model in science learning to improve students' science process skills. The development stage consists of three steps: a) designing a prototype, b) performing a formative evaluation and c) a prototype revision. Implementation stage is done through a limited trial. A limited trial was conducted on 24 and 26 August 2015 in Class VII 2 SMPN 12 Padang. The evaluation phase was conducted in the form of experiments at SMPN 1 Padang, SMPN 12 Padang and SMP National Padang. Based on the development research done, the syntax model problem solving for science learning at junior high school consists of the introduction, observation, initial problems, data collection, data organization, data analysis/generalization, and communicating.

  15. Nanomedicine: Problem Solving to Treat Cancer

    Science.gov (United States)

    Hemling, Melissa A.; Sammel, Lauren M.; Zenner, Greta; Payne, Amy C.; Crone, Wendy C.

    2006-01-01

    Many traditional classroom science and technology activities often ask students to complete prepackaged labs that ensure that everyone arrives at the same "scientifically accurate" solution or theory, which ignores the important problem-solving and creative aspects of scientific research and technological design. Students rarely have the…

  16. USING SYSTEMIC PROBLEM SOLVING (SPS) TO ASSESS ...

    African Journals Online (AJOL)

    unesco

    Also, systemic problem solving (SPS) helps students to connect chemistry concepts, and facts and covers a wide range of ... So, by using SPS we assess the student achievement in three systemic levels of learning chemistry: the macro ..... Johnstone A.H. (2000). Teaching of Chemistry – logical or psychological? CERAPIE ...

  17. Combined Approach for Solving the Electromagnetic Induction ...

    African Journals Online (AJOL)

    Nafiisah

    The entries in vector Z. ∆ are, in general, complex numbers. In a practical situation, the material distribution in the object space is unknown, and the inverse problem (or image reconstruction problem) consists in estimating it from the measurable vector Z. ∆ . Solving the general inverse problem presents a formidable difficulty ...

  18. Lions (Panthera leo) solve, learn, and remember a novel resource acquisition problem.

    Science.gov (United States)

    Borrego, Natalia; Dowling, Brian

    2016-09-01

    The social intelligence hypothesis proposes that the challenges of complex social life bolster the evolution of intelligence, and accordingly, advanced cognition has convergently evolved in several social lineages. Lions (Panthera leo) offer an ideal model system for cognitive research in a highly social species with an egalitarian social structure. We investigated cognition in lions using a novel resource task: the suspended puzzle box. The task required lions (n = 12) to solve a novel problem, learn the techniques used to solve the problem, and remember techniques for use in future trials. The majority of lions demonstrated novel problem-solving and learning; lions (11/12) solved the task, repeated success in multiple trials, and significantly reduced the latency to success across trials. Lions also demonstrated cognitive abilities associated with memory and solved the task after up to a 7-month testing interval. We also observed limited evidence for social facilitation of the task solution. Four of five initially unsuccessful lions achieved success after being partnered with a successful lion. Overall, our results support the presence of cognition associated with novel problem-solving, learning, and memory in lions. To date, our study is only the second experimental investigation of cognition in lions and further supports expanding cognitive research to lions.

  19. Testing problem solving in turkey vultures (Cathartes aura) using the string-pulling test.

    Science.gov (United States)

    Ellison, Anne Margaret; Watson, Jane; Demers, Eric

    2015-01-01

    To examine problem solving in turkey vultures (Cathartes aura), six captive vultures were presented with a string-pulling task, which involved drawing a string up to access food. This test has been used to assess cognition in many bird species. A small piece of meat suspended by a string was attached to a perch. Two birds solved the problem without apparent trial-and-error learning; a third bird solved the problem after observing a successful bird, suggesting that this individual learned from the other vulture. The remaining birds failed to complete the task. The successful birds significantly reduced the time needed to solve the task from early trials compared to late trials, suggesting that they had learned to solve the problem and improved their technique. The successful vultures solved the problem in a novel way: they pulled the string through their beak with their tongue, and may have gathered the string in their crop until the food was in reach. In contrast, ravens, parrots and finches use a stepwise process; they pull the string up, tuck it under foot, and reach down to pull up another length. As scavengers, turkey vultures use their beak for tearing and ripping at carcasses, but possess large, flat, webbed feet that are ill-suited to pulling or grasping. The ability to solve this problem and the novel approach used by the turkey vultures in this study may be a result of the unique evolutionary pressures imposed on this scavenging species.

  20. Parallel pseudospectral domain decomposition techniques

    Science.gov (United States)

    Gottlieb, David; Hirsch, Richard S.

    1989-01-01

    The influence of interface boundary conditions on the ability to parallelize pseudospectral multidomain algorithms is investigated. Using the properties of spectral expansions, a novel parallel two domain procedure is generalized to an arbitrary number of domains each of which can be solved on a separate processor. This interface boundary condition considerably simplifies influence matrix techniques.

  1. Use of model analysis to analyse Thai students’ attitudes and approaches to physics problem solving

    Science.gov (United States)

    Rakkapao, S.; Prasitpong, S.

    2018-03-01

    This study applies the model analysis technique to explore the distribution of Thai students’ attitudes and approaches to physics problem solving and how those attitudes and approaches change as a result of different experiences in physics learning. We administered the Attitudes and Approaches to Problem Solving (AAPS) survey to over 700 Thai university students from five different levels, namely students entering science, first-year science students, and second-, third- and fourth-year physics students. We found that their inferred mental states were generally mixed. The largest gap between physics experts and all levels of the students was about the role of equations and formulas in physics problem solving, and in views towards difficult problems. Most participants of all levels believed that being able to handle the mathematics is the most important part of physics problem solving. Most students’ views did not change even though they gained experiences in physics learning.

  2. Unsupervised neural networks for solving Troesch's problem

    International Nuclear Information System (INIS)

    Raja Muhammad Asif Zahoor

    2014-01-01

    In this study, stochastic computational intelligence techniques are presented for the solution of Troesch's boundary value problem. The proposed stochastic solvers use the competency of a feed-forward artificial neural network for mathematical modeling of the problem in an unsupervised manner, whereas the learning of unknown parameters is made with local and global optimization methods as well as their combinations. Genetic algorithm (GA) and pattern search (PS) techniques are used as the global search methods and the interior point method (IPM) is used for an efficient local search. The combination of techniques like GA hybridized with IPM (GA-IPM) and PS hybridized with IPM (PS-IPM) are also applied to solve different forms of the equation. A comparison of the proposed results obtained from GA, PS, IPM, PS-IPM and GA-IPM has been made with the standard solutions including well known analytic techniques of the Adomian decomposition method, the variational iterational method and the homotopy perturbation method. The reliability and effectiveness of the proposed schemes, in term of accuracy and convergence, are evaluated from the results of statistical analysis based on sufficiently large independent runs. (interdisciplinary physics and related areas of science and technology)

  3. ON THE REJECTION ABILITY REQUIRED IN MULTIPLE HYPOTHESIS TECHNIQUES

    NARCIS (Netherlands)

    Sako, H.; Kagehiro, T.; Fujisawa, H.

    2004-01-01

    The so­called multiple hypothesis technique is applied to solve a recognition problem that can be divided into at least two sub­problems. The principle of the technique is to solve the sub­problems by recognisers, a pre­recogniser and a post­recogniser, and to allow the pre­recogniser to leave

  4. Mathematical Problem Solving: A Review of the Literature.

    Science.gov (United States)

    Funkhouser, Charles

    The major perspectives on problem solving of the twentieth century are reviewed--associationism, Gestalt psychology, and cognitive science. The results of the review on teaching problem solving and the uses of computers to teach problem solving are included. Four major issues related to the teaching of problem solving are discussed: (1)…

  5. Young Children's Analogical Problem Solving: Gaining Insights from Video Displays

    Science.gov (United States)

    Chen, Zhe; Siegler, Robert S.

    2013-01-01

    This study examined how toddlers gain insights from source video displays and use the insights to solve analogous problems. Two- to 2.5-year-olds viewed a source video illustrating a problem-solving strategy and then attempted to solve analogous problems. Older but not younger toddlers extracted the problem-solving strategy depicted in the video…

  6. Learning Matlab a problem solving approach

    CERN Document Server

    Gander, Walter

    2015-01-01

    This comprehensive and stimulating introduction to Matlab, a computer language now widely used for technical computing, is based on an introductory course held at Qian Weichang College, Shanghai University, in the fall of 2014.  Teaching and learning a substantial programming language aren’t always straightforward tasks. Accordingly, this textbook is not meant to cover the whole range of this high-performance technical programming environment, but to motivate first- and second-year undergraduate students in mathematics and computer science to learn Matlab by studying representative problems, developing algorithms and programming them in Matlab. While several topics are taken from the field of scientific computing, the main emphasis is on programming. A wealth of examples are completely discussed and solved, allowing students to learn Matlab by doing: by solving problems, comparing approaches and assessing the proposed solutions.

  7. What is physics problem solving competency?

    DEFF Research Database (Denmark)

    Niss, Martin

    2018-01-01

    on the nature of physics problem- solving competency. The first, Sommerfeld’s, is a “theory first, phenomenon second” approach. Here the relevant problems originate in one of the theories of physics and the job goal of the problem- solver is to make a mathematical analysis of the suitable equation......A central goal of physics education is to teach problem-solving competency, but the nature of this competency is not well-described in the literature. The present paperarticle uses recent historical scholarship on Arnold Sommerfeld and Enrico Fermi to identify and characterize two positions......(s) and then give a qualitative analysis of the phenomenon that arise from these mathematical results. Fermi’s position is a “phenomenon first, theory second” approach, where the starting point is a physical phenomenon that is analyzed and then brought into the realm of a physics theory. The two positions...

  8. Physics solving-problem mediated by technology

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Souza

    2008-08-01

    Full Text Available We questioned the traditional practice of Physics teaching interrogating the normal procedures of solving-problem. We pointed the students passivity out, the lack of dialog interaction, the teaching-learning activity isolated from investigation, as responsible for the technological-communication non-mediation in classroom and, consequently, the lack of the problem-dialog in school process. Oriented by the investigation-action conceptions and by the problem-dialog education, we developed, established and evaluated an school object for solving-problem linked in to a teaching-learning virtual environment for the Internet, both with open sources, prioritizing empowered didactic strategies of procedures and abilities which we named as teachinginvestigation- learning in a problem perspective

  9. Derivative free Davidon-Fletcher-Powell (DFP) for solving symmetric systems of nonlinear equations

    Science.gov (United States)

    Mamat, M.; Dauda, M. K.; Mohamed, M. A. bin; Waziri, M. Y.; Mohamad, F. S.; Abdullah, H.

    2018-03-01

    Research from the work of engineers, economist, modelling, industry, computing, and scientist are mostly nonlinear equations in nature. Numerical solution to such systems is widely applied in those areas of mathematics. Over the years, there has been significant theoretical study to develop methods for solving such systems, despite these efforts, unfortunately the methods developed do have deficiency. In a contribution to solve systems of the form F(x) = 0, x ∈ Rn , a derivative free method via the classical Davidon-Fletcher-Powell (DFP) update is presented. This is achieved by simply approximating the inverse Hessian matrix with {Q}k+1-1 to θkI. The modified method satisfied the descent condition and possess local superlinear convergence properties. Interestingly, without computing any derivative, the proposed method never fail to converge throughout the numerical experiments. The output is based on number of iterations and CPU time, different initial starting points were used on a solve 40 benchmark test problems. With the aid of the squared norm merit function and derivative-free line search technique, the approach yield a method of solving symmetric systems of nonlinear equations that is capable of significantly reducing the CPU time and number of iteration, as compared to its counterparts. A comparison between the proposed method and classical DFP update were made and found that the proposed methodis the top performer and outperformed the existing method in almost all the cases. In terms of number of iterations, out of the 40 problems solved, the proposed method solved 38 successfully, (95%) while classical DFP solved 2 problems (i.e. 05%). In terms of CPU time, the proposed method solved 29 out of the 40 problems given, (i.e.72.5%) successfully whereas classical DFP solves 11 (27.5%). The method is valid in terms of derivation, reliable in terms of number of iterations and accurate in terms of CPU time. Thus, suitable and achived the objective.

  10. Ukraine's Participation In Solving Climate Change Problems

    OpenAIRE

    Irina Dubovich; Mariana Bulgakova

    2011-01-01

    Attention is paid to some problems of climate change. The main international agreements on climate change are overviewed. Ukraine's participation in solving global problems of climate change is described. Ukraine's statement about plans to reduce greenhouse gas emissions is analyzed. Characteristic of environmental political and legal prerequisites for the need to create a general agreement on environmental security of the planet – World Environmental Constitution is provided.

  11. Rational approximatons for solving cauchy problems

    Directory of Open Access Journals (Sweden)

    Veyis Turut

    2016-08-01

    Full Text Available In this letter, numerical solutions of Cauchy problems are considered by multivariate Padé approximations (MPA. Multivariate Padé approximations (MPA were applied to power series solutions of Cauchy problems that solved by using He’s variational iteration method (VIM. Then, numerical results obtained by using multivariate Padé approximations were compared with the exact solutions of Cauchy problems.

  12. Spectral-Homotopy Perturbation Method for Solving Governing MHD Jeffery-Hamel Problem

    Directory of Open Access Journals (Sweden)

    Ahmed A. Khidir

    2014-01-01

    Full Text Available We present a new modification of the homotopy perturbation method (HPM for solving nonlinear boundary value problems. The technique is based on the standard homotopy perturbation method and blending of the Chebyshev pseudospectral methods. The implementation of the new approach is demonstrated by solving the MHD Jeffery-Hamel flow and the effect of MHD on the flow has been discussed. Comparisons are made between the proposed technique, the previous studies, the standard homotopy perturbation method, and the numerical solutions to demonstrate the applicability, validity, and high accuracy of the presented approach. The results demonstrate that the new modification is more efficient and converges faster than the standard homotopy perturbation method at small orders. The MATLAB software has been used to solve all the equations in this study.

  13. An inherently parallel method for solving discretized diffusion equations

    International Nuclear Information System (INIS)

    Eccleston, B.R.; Palmer, T.S.

    1999-01-01

    A Monte Carlo approach to solving linear systems of equations is being investigated in the context of the solution of discretized diffusion equations. While the technique was originally devised decades ago, changes in computer architectures (namely, massively parallel machines) have driven the authors to revisit this technique. There are a number of potential advantages to this approach: (1) Analog Monte Carlo techniques are inherently parallel; this is not necessarily true to today's more advanced linear equation solvers (multigrid, conjugate gradient, etc.); (2) Some forms of this technique are adaptive in that they allow the user to specify locations in the problem where resolution is of particular importance and to concentrate the work at those locations; and (3) These techniques permit the solution of very large systems of equations in that matrix elements need not be stored. The user could trade calculational speed for storage if elements of the matrix are calculated on the fly. The goal of this study is to compare the parallel performance of Monte Carlo linear solvers to that of a more traditional parallelized linear solver. The authors observe the linear speedup that they expect from the Monte Carlo algorithm, given that there is no domain decomposition to cause significant communication overhead. Overall, PETSc outperforms the Monte Carlo solver for the test problem. The PETSc parallel performance improves with larger numbers of unknowns for a given number of processors. Parallel performance of the Monte Carlo technique is independent of the size of the matrix and the number of processes. They are investigating modifications to the scheme to accommodate matrix problems with positive off-diagonal elements. They are also currently coding an on-the-fly version of the algorithm to investigate the solution of very large linear systems

  14. Solving Nonlinear Euler Equations with Arbitrary Accuracy

    Science.gov (United States)

    Dyson, Rodger W.

    2005-01-01

    A computer program that efficiently solves the time-dependent, nonlinear Euler equations in two dimensions to an arbitrarily high order of accuracy has been developed. The program implements a modified form of a prior arbitrary- accuracy simulation algorithm that is a member of the class of algorithms known in the art as modified expansion solution approximation (MESA) schemes. Whereas millions of lines of code were needed to implement the prior MESA algorithm, it is possible to implement the present MESA algorithm by use of one or a few pages of Fortran code, the exact amount depending on the specific application. The ability to solve the Euler equations to arbitrarily high accuracy is especially beneficial in simulations of aeroacoustic effects in settings in which fully nonlinear behavior is expected - for example, at stagnation points of fan blades, where linearizing assumptions break down. At these locations, it is necessary to solve the full nonlinear Euler equations, and inasmuch as the acoustical energy is of the order of 4 to 5 orders of magnitude below that of the mean flow, it is necessary to achieve an overall fractional error of less than 10-6 in order to faithfully simulate entropy, vortical, and acoustical waves.

  15. Gender differences in advanced mathematical problem solving.

    Science.gov (United States)

    Gallagher, A M; De Lisi, R; Holst, P C; McGillicuddy-De Lisi, A V; Morely, M; Cahalan, C

    2000-03-01

    Strategy flexibility in mathematical problem solving was investigated. In Studies 1 and 2, high school juniors and seniors solved Scholastic Assessment Test-Mathematics (SAT-M) problems classified as conventional or unconventional. Algorithmic solution strategies were students' default choice for both types of problems across conditions that manipulated item format and solution time. Use of intuitive strategies on unconventional problems was evident only for high-ability students. Male students were more likely than female students to successfully match strategies to problem characteristics. In Study 3, a revised taxonomy of problems based on cognitive solution demands was predictive of gender differences on Graduate Record Examination-Quantitative (GRE-Q) items. Men outperformed women overall, but the difference was greater on items requiring spatial skills, shortcuts, or multiple solution paths than on problems requiring verbal skills or mastery of classroom-based content. Results suggest that strategy flexibility is a source of gender differences in mathematical ability assessed by SAT-M and GRE-Q problem solving. Copyright 2000 Academic Press.

  16. Characteristics of students in comparative problem solving

    Science.gov (United States)

    Irfan, M.; Sudirman; Rahardi, R.

    2018-01-01

    Often teachers provided examples and exercised to students with regard to comparative problems consisting of one quantity. In this study, the researchers gave the problem of comparison with the two quantities mixed. It was necessary to have a good understanding to solve this problem. This study aimed to determine whether students understand the comparison in depth and be able to solve the problem of non-routine comparison. This study used qualitative explorative methods, with researchers conducting in-depth interviews on subjects to explore the thinking process when solving comparative problems. The subject of this study was three students selected by purposive sampling of 120 students. From this research, researchers found there were three subjects with different characteristics, namely: subject 1, he did the first and second questions with methods of elimination and substitution (non-comparison); subject 2, he did the first question with the concept of comparison although the answer was wrong, and did the second question with the method of elimination and substitution (non-comparison); and subject 3, he did both questions with the concept of comparison. In the first question, he did wrong because he was unable to understand the problem, while on the second he did correctly. From the characteristics of the answers, the researchers divided into 3 groups based on thinking process, namely: blind-proportion, partial-proportion, and proportion thinking.

  17. Learning via problem solving in mathematics education

    Directory of Open Access Journals (Sweden)

    Piet Human

    2009-09-01

    Full Text Available Three forms of mathematics education at school level are distinguished: direct expository teaching with an emphasis on procedures, with the expectation that learners will at some later stage make logical and functional sense of what they have learnt and practised (the prevalent form, mathematically rigorous teaching in terms of fundamental mathematical concepts, as in the so-called “modern mathematics” programmes of the sixties, teaching and learning in the context of engaging with meaningful problems and focused both on learning to become good problem solvers (teaching for problem solving andutilising problems as vehicles for the development of mathematical knowledge andproficiency by learners (problem-centred learning, in conjunction with substantialteacher-led social interaction and mathematical discourse in classrooms.Direct expository teaching of mathematical procedures dominated in school systems after World War II, and was augmented by the “modern mathematics” movement in the period 1960-1970. The latter was experienced as a major failure, and was soon abandoned. Persistent poor outcomes of direct expository procedural teaching of mathematics for the majority of learners, as are still being experienced in South Africa, triggered a world-wide movement promoting teaching mathematics for and via problem solving in the seventies and eighties of the previous century. This movement took the form of a variety of curriculum experiments in which problem solving was the dominant classroom activity, mainly in the USA, Netherlands, France and South Africa. While initially focusing on basic arithmetic (computation with whole numbers and elementary calculus, the problem-solving movement started to address other mathematical topics (for example, elementary statistics, algebra, differential equations around the turn of the century. The movement also spread rapidly to other countries, including Japan, Singapore and Australia. Parallel with the

  18. Processes involved in solving mathematical problems

    Science.gov (United States)

    Shahrill, Masitah; Putri, Ratu Ilma Indra; Zulkardi, Prahmana, Rully Charitas Indra

    2018-04-01

    This study examines one of the instructional practices features utilized within the Year 8 mathematics lessons in Brunei Darussalam. The codes from the TIMSS 1999 Video Study were applied and strictly followed, and from the 183 mathematics problems recorded, there were 95 problems with a solution presented during the public segments of the video-recorded lesson sequences of the four sampled teachers. The analyses involved firstly, identifying the processes related to mathematical problem statements, and secondly, examining the different processes used in solving the mathematical problems for each problem publicly completed during the lessons. The findings revealed that for three of the teachers, their problem statements coded as `using procedures' ranged from 64% to 83%, while the remaining teacher had 40% of his problem statements coded as `making connections.' The processes used when solving the problems were mainly `using procedures', and none of the problems were coded as `giving results only'. Furthermore, all four teachers made use of making the relevant connections in solving the problems given to their respective students.

  19. Students’ difficulties in solving linear equation problems

    Science.gov (United States)

    Wati, S.; Fitriana, L.; Mardiyana

    2018-03-01

    A linear equation is an algebra material that exists in junior high school to university. It is a very important material for students in order to learn more advanced mathematics topics. Therefore, linear equation material is essential to be mastered. However, the result of 2016 national examination in Indonesia showed that students’ achievement in solving linear equation problem was low. This fact became a background to investigate students’ difficulties in solving linear equation problems. This study used qualitative descriptive method. An individual written test on linear equation tasks was administered, followed by interviews. Twenty-one sample students of grade VIII of SMPIT Insan Kamil Karanganyar did the written test, and 6 of them were interviewed afterward. The result showed that students with high mathematics achievement donot have difficulties, students with medium mathematics achievement have factual difficulties, and students with low mathematics achievement have factual, conceptual, operational, and principle difficulties. Based on the result there is a need of meaningfulness teaching strategy to help students to overcome difficulties in solving linear equation problems.

  20. A Novel Technique for Closed Reduction and Fixation of Paediatric Calcaneal Fracture Dislocation Injuries

    Directory of Open Access Journals (Sweden)

    Radwane Faroug

    2013-01-01

    Full Text Available Paediatric calcaneal fractures are rare injuries usually managed conservatively or with open reduction and internal fixation (ORIF. Closed reduction was previously thought to be impossible, and very few cases are reported in the literature. We report a new technique for closed reduction using Ilizarov half-rings. We report successful closed reduction and screwless fixation of an extra-articular calcaneal fracture dislocation in a 7-year-old boy. Reduction was achieved using two Ilizarov half-ring frames arranged perpendicular to each other, enabling simultaneous application of longitudinal and rotational traction. Anatomical reduction was achieved with restored angles of Bohler and Gissane. Two K-wires were the definitive fixation. Bony union with good functional outcome and minimal pain was achieved at eight-weeks follow up. ORIF of calcaneal fractures provides good functional outcome but is associated with high rates of malunion and postoperative pain. Preservation of the unique soft tissue envelope surrounding the calcaneus reduces the risk of infection. Closed reduction prevents distortion of these tissues and may lead to faster healing and mobilisation. Closed reduction and screwless fixation of paediatric calcaneal fractures is an achievable management option. Our technique has preserved the soft tissue envelope surrounding the calcaneus, has avoided retained metalwork related complications, and has resulted in a good functional outcome.

  1. Human Health Concenrs of Metalworking Fluid Components

    Science.gov (United States)

    Gerulová, Kristína; Buranská, Eva; Soldán, Maroš

    2017-06-01

    Exploration of 209 available Material safety data sheets of 85 straight oils, 46 emulsions, 51 semi-synthetics and 27 synthetics was carried out to provide a report on the most widely used components defined as dangerous substances. As many as 217 of different substances of which 15 were identified as biocides, 17 as corrosion inhibitors or neutralizing agent, 17 were lubricity improvers and 38 different base fluids, lubricity solvents or surfactants, while 93 substances were not identified specifically and 37 substances occurred only once. This article is focused on the list of base fluids in straight oils and their possible health effects.

  2. Human Health Concenrs of Metalworking Fluid Components

    Directory of Open Access Journals (Sweden)

    Gerulová Kristína

    2017-06-01

    Full Text Available Exploration of 209 available Material safety data sheets of 85 straight oils, 46 emulsions, 51 semi-synthetics and 27 synthetics was carried out to provide a report on the most widely used components defined as dangerous substances. As many as 217 of different substances of which 15 were identified as biocides, 17 as corrosion inhibitors or neutralizing agent, 17 were lubricity improvers and 38 different base fluids, lubricity solvents or surfactants, while 93 substances were not identified specifically and 37 substances occurred only once. This article is focused on the list of base fluids in straight oils and their possible health effects.

  3. The Impact of Teacher Training on Creative Writing and Problem-Solving Using Futuristic Scenarios for Creative Problem Solving and Creative Problem Solving Programs

    Science.gov (United States)

    Hayel Al-Srour, Nadia; Al-Ali, Safa M.; Al-Oweidi, Alia

    2016-01-01

    The present study aims to detect the impact of teacher training on creative writing and problem-solving using both Futuristic scenarios program to solve problems creatively, and creative problem solving. To achieve the objectives of the study, the sample was divided into two groups, the first consist of 20 teachers, and 23 teachers to second…

  4. Effects of the SOLVE Strategy on the Mathematical Problem Solving Skills of Secondary Students with Learning Disabilities

    Science.gov (United States)

    Freeman-Green, Shaqwana M.; O'Brien, Chris; Wood, Charles L.; Hitt, Sara Beth

    2015-01-01

    This study examined the effects of explicit instruction in the SOLVE Strategy on the mathematical problem solving skills of six Grade 8 students with specific learning disabilities. The SOLVE Strategy is an explicit instruction, mnemonic-based learning strategy designed to help students in solving mathematical word problems. Using a multiple probe…

  5. Application of Radiotracer Technology on Solving the Unsolved Leak in Lift Pit

    International Nuclear Information System (INIS)

    Mohd Fitri Abdul Rahman; Jaafar Abdullah; Hearie Hassan

    2016-01-01

    Radiotracers have been used in many fields to optimize processes, solve problems, improve product quality, save energy and reduce pollution. The radiotracer technology is a proven reliable technique and recognized by many sectors such as medical, industrial and environmental. In this work, an unsolved leak problem was present in lift pit within a building in Malaysia. Many techniques have applied such as dye techniques, chemical analyses and engineering plaster to overcome the problem. Unfortunately, none of the techniques solve the problem. Radiotracer was used to find the unidentified source of leak. Basically, Technetium (Tc-99m) has been injected to the several injection points and flow of the tracer was monitored with radiation detectors that have been placed at various locations. The results were successful and pinpoint the problems. (author)

  6. BACKPROPAGATION TRAINING ALGORITHM WITH ADAPTIVE PARAMETERS TO SOLVE DIGITAL PROBLEMS

    Directory of Open Access Journals (Sweden)

    R. Saraswathi

    2011-01-01

    Full Text Available An efficient technique namely Backpropagation training with adaptive parameters using Lyapunov Stability Theory for training single hidden layer feed forward network is proposed. A three-layered Feedforward neural network architecture is used to solve the selected problems. Sequential Training Mode is used to train the network. Lyapunov stability theory is employed to ensure the faster and steady state error convergence and to construct and energy surface with a single global minimum point through the adaptive adjustment of the weights and the adaptive parameter ß. To avoid local minima entrapment, an adaptive backpropagation algorithm based on Lyapunov stability theory is used. Lyapunov stability theory gives the algorithm, the efficiency of attaining a single global minimum point. The learning parameters used in this algorithm is responsible for the faster error convergence. The adaptive learning parameter used in this algorithm is chosen properly for faster error convergence. The error obtained has been asymptotically converged to zero according to Lyapunov Stability theory. The performance of the adaptive Backpropagation algorithm is measured by solving parity problem, half adder and full adder problems.

  7. Computer-Presented Organizational/Memory Aids as Instruction for Solving Pico-Fomi Problems.

    Science.gov (United States)

    Steinberg, Esther R.; And Others

    1985-01-01

    Describes investigation of effectiveness of computer-presented organizational/memory aids (matrix and verbal charts controlled by computer or learner) as instructional technique for solving Pico-Fomi problems, and the acquisition of deductive inference rules when such aids are present. Results indicate chart use control should be adapted to…

  8. The "Iron Inventor": Using Creative Problem Solving to Spur Student Creativity

    Science.gov (United States)

    Lee, Seung Hwan; Hoffman, K. Douglas

    2014-01-01

    Based on the popular television show the "Iron Chef," an innovative marketing activity called the "Iron Inventor" is introduced. Using the creative problem-solving approach and active learning techniques, the Iron Inventor facilitates student learning pertaining to the step-by-step processes of creating a new product and…

  9. SCAMPER and Creative Problem Solving in Political Science: Insights from Classroom Observation

    Science.gov (United States)

    Radziszewski, Elizabeth

    2017-01-01

    This article describes the author's experience using SCAMPER, a creativity-building technique, in a creative problem-solving session that was conducted in an environmental conflict course to generate ideas for managing postconflict stability. SCAMPER relies on cues to help students connect ideas from different domains of knowledge, explore random…

  10. Application of NASA management approach to solve complex problems on earth

    Science.gov (United States)

    Potate, J. S.

    1972-01-01

    The application of NASA management approach to solving complex problems on earth is discussed. The management of the Apollo program is presented as an example of effective management techniques. Four key elements of effective management are analyzed. Photographs of the Cape Kennedy launch sites and supporting equipment are included to support the discussions.

  11. Effectiveness of Computer-Assisted STAD Cooperative Learning Strategy on Physics Problem Solving, Achievement and Retention

    Science.gov (United States)

    Gambari, Amosa Isiaka; Yusuf, Mudasiru Olalere

    2015-01-01

    This study investigated the effectiveness of computer-assisted Students' Team Achievement Division (STAD) cooperative learning strategy on physics problem solving, students' achievement and retention. It also examined if the student performance would vary with gender. Purposive sampling technique was used to select two senior secondary schools…

  12. Application of Local Fractional Series Expansion Method to Solve Klein-Gordon Equations on Cantor Sets

    Directory of Open Access Journals (Sweden)

    Ai-Min Yang

    2014-01-01

    Full Text Available We use the local fractional series expansion method to solve the Klein-Gordon equations on Cantor sets within the local fractional derivatives. The analytical solutions within the nondifferential terms are discussed. The obtained results show the simplicity and efficiency of the present technique with application to the problems of the liner differential equations on Cantor sets.

  13. Hodograph: A useful geometrical tool for solving some difficult problems in dynamics

    Science.gov (United States)

    Apostolatos, Theocharis A.

    2003-03-01

    The hodograph is very useful for solving complicated problems in dynamics. By simple geometrical arguments students can directly obtain the answer to problems that would otherwise be complicated exercises in algebra. Although beyond the level of undergraduates, we also use the hodograph to calculate by variational geometrical techniques, the well-known brachistochrone curve, thus illustrating this approach.

  14. Teaching Creative Problem Solving Methods to Undergraduate Economics and Business Students

    Science.gov (United States)

    Cancer, Vesna

    2014-01-01

    This paper seeks to explore the need for and possibility of teaching current and potential problem solvers--undergraduate students in the economic and business field to define problems, to generate and choose creative and useful ideas and to verify them. It aims to select an array of quick and easy-to-use creative problem solving (CPS) techniques.…

  15. Factors Influencing Mathematic Problem-Solving Ability of Sixth Grade Students

    Science.gov (United States)

    Pimta, Sakorn; Tayraukham, Sombat; Nuangchalerm, Prasart

    2009-01-01

    Problem statement: This study aims to investigate factors influencing mathematic problem-solving ability of sixth grade students. One thousand and twenty eight of sixth grade students, studying in the second semester of academic year 2007 were sampled by stratified random sampling technique. Approach: The research instruments used in the study…

  16. Solucion de Problemas y Procesos Cognoscitivos (Problem Solving and Cognitive Processes). Publication No. 41.

    Science.gov (United States)

    Rimoldi, Horacio J. A.

    The study of problem solving is made through the analysis of the process that leads to the final answer. The type of information obtained through the study of the process is compared with the information obtained by studying the final answer. The experimental technique used permits to identify the sequence of questions (tactics) that subjects ask…

  17. Adapting a Problem-Solving Approach to Teaching Mathematics to Students with Mild Disabilities.

    Science.gov (United States)

    Salend, Spencer J.; Hofstetter, Elaine

    1996-01-01

    Guidelines for implementing a problem-solving approach to teaching mathematics concepts and skills to students with mild disabilities include: establish connections to daily life; use visual presentations; use manipulatives; use peer-mediated instruction; provide models, cues, and prompts; teach self-management techniques and learning strategies;…

  18. A Computer Algebra Approach to Solving Chemical Equilibria in General Chemistry

    Science.gov (United States)

    Kalainoff, Melinda; Lachance, Russ; Riegner, Dawn; Biaglow, Andrew

    2012-01-01

    In this article, we report on a semester-long study of the incorporation into our general chemistry course, of advanced algebraic and computer algebra techniques for solving chemical equilibrium problems. The method presented here is an alternative to the commonly used concentration table method for describing chemical equilibria in general…

  19. A Limited Memory BFGS Method for Solving Large-Scale Symmetric Nonlinear Equations

    Directory of Open Access Journals (Sweden)

    Xiangrong Li

    2014-01-01

    Full Text Available A limited memory BFGS (L-BFGS algorithm is presented for solving large-scale symmetric nonlinear equations, where a line search technique without derivative information is used. The global convergence of the proposed algorithm is established under some suitable conditions. Numerical results show that the given method is competitive to those of the normal BFGS methods.

  20. Modified Halfspace-Relaxation Projection Methods for Solving the Split Feasibility Problem

    Directory of Open Access Journals (Sweden)

    Min Li

    2012-01-01

    Full Text Available This paper presents modified halfspace-relaxation projection (HRP methods for solving the split feasibility problem (SFP. Incorporating with the techniques of identifying the optimal step length with positive lower bounds, the new methods improve the efficiencies of the HRP method (Qu and Xiu (2008. Some numerical results are reported to verify the computational preference.

  1. USING SIX THINKING HATS AS A TOOL FOR LATERAL THINKING IN ORGANIZATIONAL PROBLEM SOLVING

    OpenAIRE

    Dr. P. S. Aithal; Dr. P. M. Suresh Kumar

    2016-01-01

    Six thinking hats is recently introduced technique which outlines different thinking styles required by an individual while analysing a given problem in an effective way. The technique correlates different thinking styles used in a systematic problem-solving procedure with different coloured hats. Alternately, by conceptualizing each type of hat, the person focuses on the style of thinking associated with each colour so that the problem can be analysed from different angles and frame of refer...

  2. Solving Multiple Timetabling Problems at Danish High Schools

    DEFF Research Database (Denmark)

    Kristiansen, Simon

    Planning problems at educational institutions are often time-consuming and complex tasks. Educational planning problems are studied using operational research techniques, which have been used with success and resulting in great improvements on the field. Educational planning problems are often...... in High School Timetabling has mainly been concentrated on local problems until recently. By the creation of an XML-format, XHSTT, and applicable wide ranging benchmark instances, it is been possible to solve the more generalized High School Timetabling problem. The first part of this thesis presents two...... show that by using a sequential method it is possible to gain much better results. The last part of the thesis is concerned the Meeting Planning Problem and presented with two papers. The Consultation Timetabling Problem is one of the minor, but still time-consuming, planning problems at the Danish...

  3. 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

  4. Problem-solving phase transitions during team collaboration

    DEFF Research Database (Denmark)

    Wiltshire, Travis; Butner, Jonathan E.; Fiore, Stephen M.

    2017-01-01

    ) with dynamical systems theory suggesting that when a system is undergoing a phase transition it should exhibit a peak in entropy and that entropy levels should also relate to team performance. Communications from 40 teams that collaborated on a complex problem were coded for occurrence of problem......-solving processes. We applied a sliding window entropy technique to each team's communications and specified criteria for (a) identifying data points that qualify as peaks and (b) determining which peaks were robust. We used multilevel modeling, and provide a qualitative example, to evaluate whether phases exhibit...... phases. Peaks in entropy thus corresponded to qualitative shifts in teams’ CPS communications, providing empirical evidence that teams exhibit phase transitions during CPS. Also, lower average levels of entropy at the phase transition points predicted better CPS performance. We specify future directions...

  5. Neural bases for basic processes in heuristic problem solving: Take solving Sudoku puzzles as an example.

    Science.gov (United States)

    Qin, Yulin; Xiang, Jie; Wang, Rifeng; Zhou, Haiyan; Li, Kuncheng; Zhong, Ning

    2012-12-01

    Newell and Simon postulated that the basic steps in human problem-solving involve iteratively applying operators to transform the state of the problem to eventually achieve a goal. To check the neural basis of this framework, the present study focused on the basic processes in human heuristic problem-solving that the participants identified the current problem state and then recalled and applied the corresponding heuristic rules to change the problem state. A new paradigm, solving simplified Sudoku puzzles, was developed for an event-related functional magnetic resonance imaging (fMRI) study in problem solving. Regions of interest (ROIs), including the left prefrontal cortex, the bilateral posterior parietal cortex, the anterior cingulated cortex, the bilateral caudate nuclei, the bilateral fusiform, as well as the bilateral frontal eye fields, were found to be involved in the task. To obtain convergent evidence, in addition to traditional statistical analysis, we used the multivariate voxel classification method to check the accuracy of the predictions for the condition of the task from the blood oxygen level dependent (BOLD) response of the ROIs, using a new classifier developed in this study for fMRI data. To reveal the roles that the ROIs play in problem solving, we developed an ACT-R computational model of the information-processing processes in human problem solving, and tried to predict the BOLD response of the ROIs from the task. Advances in human problem-solving research after Newell and Simon are then briefly discussed. © 2012 The Institute of Psychology, Chinese Academy of Sciences and Blackwell Publishing Asia Pty Ltd.

  6. The Role of Self Efficacy Towards Mathematical Problem Solving Ability in Terms of Positive Thinking Ability

    Directory of Open Access Journals (Sweden)

    Rahmawati Yuliyani

    2017-11-01

    Full Text Available This research aims to know the influence of the role of self efficacy towards solving math problems in terms of positive thinking. The method used was survey methods with quantitative approach and hypothesis testing using path analysis. Large sample as many as 140 students, with sampling the sampling technique used was saturated. The results of hypothesis testing indicate that: 1 there is a significant direct influence on self efficacy against the ability of solving math problems, with the line coefficient of 0.187 and contribute directly towards the ability of self efficacy the mathematical problem solving of 3.50%. 2 there are no significant direct influence positive thinking towards mathematical problem solving ability, with the line coefficient of 0.034 and direct contribution towards positive thinking ability of solving math problems very small even barely contribute, only amounted to 0.12%. 3 there is a significant direct influence on self efficacy against positive thinking, with a coefficient of line of direct contributions and 0.181 self-efficacy (self efficacy toward positive thinking of 3.27%. 4 there were no significant effects of self efficacy against mathematical problem solving ability through positive thinking, with the line coefficient of 0.006.

  7. Individual differences in solving arithmetic word problems

    Science.gov (United States)

    2013-01-01

    Background With the present functional magnetic resonance imaging (fMRI) study at 3 T, we investigated the neural correlates of visualization and verbalization during arithmetic word problem solving. In the domain of arithmetic, visualization might mean to visualize numbers and (intermediate) results while calculating, and verbalization might mean that numbers and (intermediate) results are verbally repeated during calculation. If the brain areas involved in number processing are domain-specific as assumed, that is, that the left angular gyrus (AG) shows an affinity to the verbal domain, and that the left and right intraparietal sulcus (IPS) shows an affinity to the visual domain, the activation of these areas should show a dependency on an individual’s cognitive style. Methods 36 healthy young adults participated in the fMRI study. The participants habitual use of visualization and verbalization during solving arithmetic word problems was assessed with a short self-report assessment. During the fMRI measurement, arithmetic word problems that had to be solved by the participants were presented in an event-related design. Results We found that visualizers showed greater brain activation in brain areas involved in visual processing, and that verbalizers showed greater brain activation within the left angular gyrus. Conclusions Our results indicate that cognitive styles or preferences play an important role in understanding brain activation. Our results confirm, that strong visualizers use mental imagery more strongly than weak visualizers during calculation. Moreover, our results suggest that the left AG shows a specific affinity to the verbal domain and subserves number processing in a modality-specific way. PMID:23883107

  8. SOLVING GLOBAL PROBLEMS USING COLLABORATIVE DESIGN PROCESSES

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Mejborn, Christina Okai

    2011-01-01

    In this paper we argue that use of collaborative design processes is a powerful means of bringing together different stakeholders and generating ideas in complex design situations. The collaborative design process was used in a workshop with international participants where the goal was to propose...... forward proposed solutions for how to design, brand and make business models for how to solve aspects of the sanitation problem. The workshop showed that it was possible to work freely with such a taboo topic and that in particular the use of visualisation tools, i.e. drawing posters and building simple...

  9. SOLVING GLOBAL PROBLEMS USING COLLABORATIVE DESIGN PROCESSES

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Mejborn, Christina Okai

    2011-01-01

    In this paper we argue that use of collaborative design processes is a powerful means of bringing together different stakeholders and generating ideas in complex design situations. The collaborative design process was used in a workshop with international participants where the goal was to propose...... new solutions that would help solve the global problem of sanitation. Lack of sanitation is a problem for 42% of the world’s population but it is also a taboo topic that only very few people will engage in. In the one-day workshop participants from very different areas came together and brought...

  10. Programming languages for business problem solving

    CERN Document Server

    Wang, Shouhong

    2007-01-01

    It has become crucial for managers to be computer literate in today's business environment. It is also important that those entering the field acquire the fundamental theories of information systems, the essential practical skills in computer applications, and the desire for life-long learning in information technology. Programming Languages for Business Problem Solving presents a working knowledge of the major programming languages, including COBOL, C++, Java, HTML, JavaScript, VB.NET, VBA, ASP.NET, Perl, PHP, XML, and SQL, used in the current business computing environment. The book examin

  11. Solving jigsaw puzzles using image features

    DEFF Research Database (Denmark)

    Nielsen, Ture R.; Drewsen, Peter; Hansen, Klaus

    2008-01-01

    In this article, we describe a method for automatic solving of the jigsaw puzzle problem based on using image features instead of the shape of the pieces. The image features are used for obtaining an accurate measure for edge similarity to be used in a new edge matching algorithm. The algorithm...... algorithm which exploits the divide and conquer paradigm to reduce the combinatorially complex problem by classifying the puzzle pieces and comparing pieces drawn from the same group. The paper includes a brief preliminary investigation of some image features used in the classification....

  12. Solving crystal structures from neutron diffraction data

    International Nuclear Information System (INIS)

    Wilson, C.C.

    1987-07-01

    In order to pursue crystal structure determination using neutron diffraction data, and given the wide experience available of solving structures using X-ray data, the codes used in X-ray structural analysis should be adapted to the different requirements of a neutron experiment. Modifications have been made to a direct methods program MITHRIL and to a Patterson methods program PATMET to incorporate into these the features of neutron rather than X-ray diffraction. While to date these modifications have been fairly straightforward and many sophistications remain to be exploited, results obtained from the neutron versions of both programs are promising. (author)

  13. The development and nature of problem-solving among first-semester calculus students

    Science.gov (United States)

    Dawkins, Paul Christian; Mendoza Epperson, James A.

    2014-08-01

    This study investigates interactions between calculus learning and problem-solving in the context of two first-semester undergraduate calculus courses in the USA. We assessed students' problem-solving abilities in a common US calculus course design that included traditional lecture and assessment with problem-solving-oriented labs. We investigate this blended instruction as a local representative of the US calculus reform movements that helped foster it. These reform movements tended to emphasize problem-solving as well as multiple mathematical registers and quantitative modelling. Our statistical analysis reveals the influence of the blended traditional/reform calculus instruction on students' ability to solve calculus-related, non-routine problems through repeated measures over the semester. The calculus instruction in this study significantly improved students' performance on non-routine problems, though performance improved more regarding strategies and accuracy than it did for drawing conclusions and providing justifications. We identified problem-solving behaviours that characterized top performance or attrition in the course. Top-performing students displayed greater algebraic proficiency, calculus skills, and more general heuristics than their peers, but overused algebraic techniques even when they proved cumbersome or inappropriate. Students who subsequently withdrew from calculus often lacked algebraic fluency and understanding of the graphical register. The majority of participants, when given a choice, relied upon less sophisticated trial-and-error approaches in the numerical register and rarely used the graphical register, contrary to the goals of US calculus reform. We provide explanations for these patterns in students' problem-solving performance in view of both their preparation for university calculus and the courses' assessment structure, which preferentially rewarded algebraic reasoning. While instruction improved students' problem-solving

  14. Are Multi-criteria Decision Making Techniques Useful for Solving Corporate Finance Problems? A Bibliometric Analysis || ¿Son adecuadas las técnicas de decisión multicriterio para resolver los problemas financieros corporativos? Un análisis bibliométrico

    Directory of Open Access Journals (Sweden)

    Guerrero-Baena, M. Dolores

    2014-06-01

    Full Text Available Corporate financial decision making processes (selection of investments and funding sources are becoming increasingly complex because of the growing number of conflicting criteria that need to be considered. The main aim of this paper is to perform a bibliometric analysis of the international research on the application of multi-criteria decision making (MCDM techniques to corporate finance issues during the period 1980-2012. A total of 347 publications from the Scopus database have been compiled, classified and analysed. The results obtained confirm: a an increase in the importance of MCDM in corporate finance; b the relevance of MCDM techniques in capital budgeting processes (fixed assets investment and in the assessment of firms' economic and financial performance; c the techniques based on the multiple attribute utility theory (MAUT are the most popular in complex decision making situations as they are very simple to implement. || Los procesos de decisión de selección de inversiones y de las fuentes de financiación de las empresas se caracterizan por una creciente complejidad, dada la confluencia del cada vez mayor número de criterios a considerar. El objetivo de este trabajo es realizar un análisis bibliométrico de la producción científica internacional que ha abordado la problemática asociada a las finanzas corporativas mediante la implementación del paradigma de Decisión Multicriterio (MCDM durante el periodo 1980-2012. Un total de 347 publicaciones han sido recopiladas de la base de datos de Scopus, clasificadas y analizadas. De los resultados obtenidos cabe destacar lo siguiente: a se ha producido un considerable incremento del uso de las técnicas multicriterio en finanzas corporativas; b las técnicas MCDM se han empleado fundamentalmente en la selección de inversiones productivas, evidenciándose igualmente su utilidad para la evaluación de la situación económico-financiera de las empresas; c las técnicas basadas en

  15. Dismantling techniques

    International Nuclear Information System (INIS)

    Wiese, E.

    1998-01-01

    Most of the dismantling techniques used in a Decontamination and Dismantlement (D and D) project are taken from conventional demolition practices. Some modifications to the techniques are made to limit exposure to the workers or to lessen the spread of contamination to the work area. When working on a D and D project, it is best to keep the dismantling techniques and tools as simple as possible. The workers will be more efficient and safer using techniques that are familiar to them. Prior experience with the technique or use of mock-ups is the best way to keep workers safe and to keep the project on schedule

  16. Comprehension and computation in Bayesian problem solving

    Directory of Open Access Journals (Sweden)

    Eric D. Johnson

    2015-07-01

    Full Text Available Humans have long been characterized as poor probabilistic reasoners when presented with explicit numerical information. Bayesian word problems provide a well-known example of this, where even highly educated and cognitively skilled individuals fail to adhere to mathematical norms. It is widely agreed that natural frequencies can facilitate Bayesian reasoning relative to normalized formats (e.g. probabilities, percentages, both by clarifying logical set-subset relations and by simplifying numerical calculations. Nevertheless, between-study performance on transparent Bayesian problems varies widely, and generally remains rather unimpressive. We suggest there has been an over-focus on this representational facilitator (i.e. transparent problem structures at the expense of the specific logical and numerical processing requirements and the corresponding individual abilities and skills necessary for providing Bayesian-like output given specific verbal and numerical input. We further suggest that understanding this task-individual pair could benefit from considerations from the literature on mathematical cognition, which emphasizes text comprehension and problem solving, along with contributions of online executive working memory, metacognitive regulation, and relevant stored knowledge and skills. We conclude by offering avenues for future research aimed at identifying the stages in problem solving at which correct versus incorrect reasoners depart, and how individual difference might influence this time point.

  17. Back to Basics: Solving Games with SAT

    Directory of Open Access Journals (Sweden)

    QUER, S.

    2016-08-01

    Full Text Available Games became popular, within the formal verification community, after their application to automatic synthesis of circuits from specifications, and they have been receiving more and more attention since then. This paper focuses on coding the "Sokoban" puzzle, i.e., a very complex single-player strategy game. We show how its solution can be encoded and represented as a Bounded Model Checking problem, and then solved with a SAT solver. After that, to cope with very complex instances of the game, we propose two different ad-hoc divide-and-conquer strategies. Those strategies, somehow similar to state-of-the-art abstraction-and-refinement schemes, are able to decompose deep Bounded Model Checking instances into easier subtasks, trading-off between efficiency and completeness. We analyze a vast set of difficult hard-to-solve benchmark games, trying to push forward the applicability of state-of-the-art SAT solvers in the field. Those results show that games may provide one of the next frontier for the SAT community.

  18. A Flipped Pedagogy for Expert Problem Solving

    Science.gov (United States)

    Pritchard, David

    The internet provides free learning opportunities for declarative (Wikipedia, YouTube) and procedural (Kahn Academy, MOOCs) knowledge, challenging colleges to provide learning at a higher cognitive level. Our ``Modeling Applied to Problem Solving'' pedagogy for Newtonian Mechanics imparts strategic knowledge - how to systematically determine which concepts to apply and why. Declarative and procedural knowledge is learned online before class via an e-text, checkpoint questions, and homework on edX.org (see http://relate.mit.edu/physicscourse); it is organized into five Core Models. Instructors then coach students on simple ``touchstone problems'', novel exercises, and multi-concept problems - meanwhile exercising three of the four C's: communication, collaboration, critical thinking and problem solving. Students showed 1.2 standard deviations improvement on the MIT final exam after three weeks instruction, a significant positive shift in 7 of the 9 categories in the CLASS, and their grades improved by 0.5 standard deviation in their following physics course (Electricity and Magnetism).

  19. Neural correlates of mathematical problem solving.

    Science.gov (United States)

    Lin, Chun-Ling; Jung, Melody; Wu, Ying Choon; She, Hsiao-Ching; Jung, Tzyy-Ping

    2015-03-01

    This study explores electroencephalography (EEG) brain dynamics associated with mathematical problem solving. EEG and solution latencies (SLs) were recorded as 11 neurologically healthy volunteers worked on intellectually challenging math puzzles that involved combining four single-digit numbers through basic arithmetic operators (addition, subtraction, division, multiplication) to create an arithmetic expression equaling 24. Estimates of EEG spectral power were computed in three frequency bands - θ (4-7 Hz), α (8-13 Hz) and β (14-30 Hz) - over a widely distributed montage of scalp electrode sites. The magnitude of power estimates was found to change in a linear fashion with SLs - that is, relative to a base of power spectrum, theta power increased with longer SLs, while alpha and beta power tended to decrease. Further, the topographic distribution of spectral fluctuations was characterized by more pronounced asymmetries along the left-right and anterior-posterior axes for solutions that involved a longer search phase. These findings reveal for the first time the topography and dynamics of EEG spectral activities important for sustained solution search during arithmetical problem solving.

  20. Using qualitative problem-solving strategies to highlight the role of conceptual knowledge in solving problems

    Science.gov (United States)

    Leonard, William J.; Dufresne, Robert J.; Mestre, Jose P.

    1996-12-01

    We report on the use of qualitative problem-solving strategies in teaching an introductory, calculus-based physics course as a means of highlighting the role played by conceptual knowledge in solving problems. We found that presenting strategies during lectures and in homework solutions provides an excellent opportunity to model for students the type of concept-based, qualitative reasoning that is valued in our profession, and that student-generated strategies serve a diagnostic function by providing instructors with insights on students' conceptual understanding and reasoning. Finally, we found strategies to be effective pedagogical tools for helping students both to identify principles that could be applied to solve specific problems, as well as to recall the major principles covered in the course months after it was over.

  1. OpenMP for 3D potential boundary value problems solved by PIES

    Science.gov (United States)

    KuŻelewski, Andrzej; Zieniuk, Eugeniusz

    2016-06-01

    The main purpose of this paper is examination of an application of modern parallel computing technique OpenMP to speed up the calculation in the numerical solution of parametric integral equations systems (PIES). The authors noticed, that solving more complex boundary problems by PIES sometimes requires large computing time. This paper presents the use of OpenMP and fast C++ linear algebra library Armadillo for boundary value problems modelled by 3D Laplace's equation and solved using PIES. The testing example shows that the use of mentioned technologies significantly increases speed of calculations in PIES.

  2. Mathematical problem solving ability of sport students in the statistical study

    Science.gov (United States)

    Sari, E. F. P.; Zulkardi; Putri, R. I. I.

    2017-12-01

    This study aims to determine the problem-solving ability of sport students of PGRI Palembang semester V in the statistics course. Subjects in this study were sport students of PGRI Palembang semester V which amounted to 31 people. The research method used is quasi experiment type one case shoot study. Data collection techniques in this study use the test and data analysis used is quantitative descriptive statistics. The conclusion of this study shown that the mathematical problem solving ability of PGRI Palembang sport students of V semester in the statistical course is categorized well with the average of the final test score of 80.3.

  3. Perspectives of natural isotopes application for solving hydrogeological problems of mineral deposits

    International Nuclear Information System (INIS)

    Rozkowski, A.

    1978-01-01

    Results of hydrogeological studies made with use of natural isotopes and carried out within the Lublin Coal Field are presented in the paper. The studies have proved advantageous possibilities of isotope technique application for solving the hydrogeological problems of mineral deposits. Examination of isotope relations in ground waters complements traditional hydrogeological methods. This trend of complex investigations enables solving some peculiar hydrodynamic and hydrochemical problems. Exact recognition of these conditions is required to elaborate out proper prognosis on water content degree in given deposit and on value of ground water inflow into areas of designed mines. (author)

  4. A Genetic Algorithm Based Approach for Solving the Minimum Dominating Set of Queens Problem

    Directory of Open Access Journals (Sweden)

    Saad Alharbi

    2017-01-01

    Full Text Available In the field of computing, combinatorics, and related areas, researchers have formulated several techniques for the Minimum Dominating Set of Queens Problem (MDSQP pertaining to the typical chessboard based puzzles. However, literature shows that limited research has been carried out to solve the MDSQP using bioinspired algorithms. To fill this gap, this paper proposes a simple and effective solution based on genetic algorithms to solve this classical problem. We report results which demonstrate that near optimal solutions have been determined by the GA for different board sizes ranging from 8 × 8 to 11 × 11.

  5. DEMONSTRATION COMPUTER MODELS USE WHILE SOLVING THE BUILDING OF THE CUT OF THE CYLINDER

    Directory of Open Access Journals (Sweden)

    Inna O. Gulivata

    2010-10-01

    Full Text Available Relevance of material presented in the article is the use of effective methods to illustrate the geometric material for the development of spatial imagination of students. As one of the ways to improve problem solving offer to illustrate the use of display computer model (DCM investigated objects created by the software environment PowerPoint. The technique of applying DCM while solving the problems to build a section of the cylinder makes it allows to build effective learning process and promotes the formation of spatial representations of students taking into account their individual characteristics and principles of differentiated instruction.

  6. Description of Student’s Metacognitive Ability in Understanding and Solving Mathematics Problem

    Science.gov (United States)

    Ahmad, Herlina; Febryanti, Fatimah; Febryanti, Fatimah; Muthmainnah

    2018-01-01

    This research was conducted qualitative which was aim to describe metacognitive ability to understand and solve the problems of mathematics. The subject of the research was the first year students at computer and networking department of SMK Mega Link Majene. The sample was taken by purposive sampling technique. The data obtained used the research instrument based on the form of students achievements were collected by using test of student’s achievement and interview guidance. The technique of collecting data researcher had observation to ascertain the model that used by teacher was teaching model of developing metacognitive. The technique of data analysis in this research was reduction data, presentation and conclusion. Based on the whole findings in this study it was shown that student’s metacognitive ability generally not develops optimally. It was because of limited scope of the materials, and cognitive teaching strategy handled by verbal presentation and trained continuously in facing cognitive tasks, such as understanding and solving problem.

  7. A review on application of neural networks and fuzzy logic to solve hydrothermal scheduling problem

    International Nuclear Information System (INIS)

    Haroon, S.; Malik, T.N.; Zafar, S.

    2014-01-01

    Electrical power system is highly complicated having hydro and thermal mix with large number of machines. To reduce power production cost, hydro and thermal resources are mixed. Hydrothermal scheduling is the optimal coordination of hydro and thermal plants to meet the system load demand at minimum possible operational cost while satisfying the system constraints. Hydrothermal scheduling is dynamic, large scale, non-linear and non-convex optimization problem. The classical techniques have failed in solving such problem. Artificial Intelligence Tools based techniques are used now a day to solve this complex optimization problem because of their no requirements on the nature of the problem. The aim of this research paper is to provide a comprehensive survey of literature related to both Artificial Neural Network (ANN) and Fuzzy Logic (FL) as effective optimization algorithms for the hydrothermal scheduling problem. The outcomes along with the merits and demerits of individual techniques are also discussed. (author)

  8. Spontaneous gestures influence strategy choices in problem solving.

    Science.gov (United States)

    Alibali, Martha W; Spencer, Robert C; Knox, Lucy; Kita, Sotaro

    2011-09-01

    Do gestures merely reflect problem-solving processes, or do they play a functional role in problem solving? We hypothesized that gestures highlight and structure perceptual-motor information, and thereby make such information more likely to be used in problem solving. Participants in two experiments solved problems requiring the prediction of gear movement, either with gesture allowed or with gesture prohibited. Such problems can be correctly solved using either a perceptual-motor strategy (simulation of gear movements) or an abstract strategy (the parity strategy). Participants in the gesture-allowed condition were more likely to use perceptual-motor strategies than were participants in the gesture-prohibited condition. Gesture promoted use of perceptual-motor strategies both for participants who talked aloud while solving the problems (Experiment 1) and for participants who solved the problems silently (Experiment 2). Thus, spontaneous gestures influence strategy choices in problem solving.

  9. Applying FOCUS-PDCA to solve clinical problems.

    Science.gov (United States)

    Redick, E L

    1999-01-01

    Many methods have been proposed for solving complex or multifaceted clinical problems in a logical, systematic, and accurate way. This article describes one method of step-by-step problem solving and how to apply it to a clinical situation.

  10. The direct algorithm for solving of the graph isomorphism problem

    OpenAIRE

    Faizullin, Rashit T.; Prolubnikov, Alexander V.

    2005-01-01

    We propose an algorithm for solving of the graph isomorphism problem. Also, we introduce the new class of graphs for which the graph isomorphism problem can be solved polynomially using the algorithm.

  11. A Decision Support System for Solving Multiple Criteria Optimization Problems

    Science.gov (United States)

    Filatovas, Ernestas; Kurasova, Olga

    2011-01-01

    In this paper, multiple criteria optimization has been investigated. A new decision support system (DSS) has been developed for interactive solving of multiple criteria optimization problems (MOPs). The weighted-sum (WS) approach is implemented to solve the MOPs. The MOPs are solved by selecting different weight coefficient values for the criteria…

  12. Teaching Young Children Interpersonal Problem-Solving Skills

    Science.gov (United States)

    Joseph, Gail E.; Strain, Phillip S.

    2010-01-01

    Learning how to problem solve is one of the key developmental milestones in early childhood. Children's problem-solving skills represent a key feature in the development of social competence. Problem solving allows children to stay calm during difficult situations, repair social relations quickly, and get their needs met in ways that are safe and…

  13. Tracer Evolution at High Latitudes in Winter (SOLVE)

    Science.gov (United States)

    Plumb, R. Alan

    2001-01-01

    Prior to the SOLVE deployment, we modified and ran a chemical transport model (CTM) to set up a stratospheric climatology for 1 September 1999. During and immediately following the SOLVE deployments, we ran the model in near-real-time and used these results in conjunction with SOLVE observations to draw conclusions about stratospheric transport.

  14. Translation among Symbolic Representations in Problem-Solving. Revised.

    Science.gov (United States)

    Shavelson, Richard J.; And Others

    This study investigated the relationships among the symbolic representation of problems given to students to solve, the mental representations they use to solve the problems, and the accuracy of their solutions. Twenty eleventh-grade science students were asked to think aloud as they solved problems on the ideal gas laws. The problems were…

  15. Solving the minimum flow problem with interval bounds and flows

    Indian Academy of Sciences (India)

    and Ciurea et al (2008b) solved the minimum flow problem for bipartite networks, and Ciurea. & Deaconu (2007) solved the ... In Ghiyasvand (2011), a new method to solve the minimum cost flow problem with interval .... multiplication of convex sets, when the fuzzification uses Definition 1 for max–min and order operations.

  16. The Influence of Cognitive Abilities on Mathematical Problem Solving Performance

    Science.gov (United States)

    Bahar, Abdulkadir

    2013-01-01

    Problem solving has been a core theme in education for several decades. Educators and policy makers agree on the importance of the role of problem solving skills for school and real life success. A primary purpose of this study was to investigate the influence of cognitive abilities on mathematical problem solving performance of students. The…

  17. The Design Process for "PLATO[R] Math Problem Solving."

    Science.gov (United States)

    Mulcahy, Robert

    2001-01-01

    PLATO Learning, Inc., a developer of computer-based instruction, recently released "Math Problem Solving." This product was designed to teach strategies for solving math problems, and consists of 19 problem-solving activities, ranging from basic math to algebra. Each activity includes tools to help find a solution and rule-based coaching to…

  18. Thinking Process of Naive Problem Solvers to Solve Mathematical Problems

    Science.gov (United States)

    Mairing, Jackson Pasini

    2017-01-01

    Solving problems is not only a goal of mathematical learning. Students acquire ways of thinking, habits of persistence and curiosity, and confidence in unfamiliar situations by learning to solve problems. In fact, there were students who had difficulty in solving problems. The students were naive problem solvers. This research aimed to describe…

  19. Modeling Regular Replacement for String Constraint Solving

    Science.gov (United States)

    Fu, Xiang; Li, Chung-Chih

    2010-01-01

    Bugs in user input sanitation of software systems often lead to vulnerabilities. Among them many are caused by improper use of regular replacement. This paper presents a precise modeling of various semantics of regular substitution, such as the declarative, finite, greedy, and reluctant, using finite state transducers (FST). By projecting an FST to its input/output tapes, we are able to solve atomic string constraints, which can be applied to both the forward and backward image computation in model checking and symbolic execution of text processing programs. We report several interesting discoveries, e.g., certain fragments of the general problem can be handled using less expressive deterministic FST. A compact representation of FST is implemented in SUSHI, a string constraint solver. It is applied to detecting vulnerabilities in web applications

  20. Data completion problems solved as Nash games

    International Nuclear Information System (INIS)

    Habbal, A; Kallel, M

    2012-01-01

    The Cauchy problem for an elliptic operator is formulated as a two-player Nash game. Player (1) is given the known Dirichlet data, and uses as strategy variable the Neumann condition prescribed over the inaccessible part of the boundary. Player (2) is given the known Neumann data, and plays with the Dirichlet condition prescribed over the inaccessible boundary. The two players solve in parallel the associated Boundary Value Problems. Their respective objectives involve the gap between the non used Neumann/Dirichlet known data and the traces of the BVP's solutions over the accessible boundary, and are coupled through a difference term. We prove the existence of a unique Nash equilibrium, which turns out to be the reconstructed data when the Cauchy problem has a solution. We also prove that the completion algorithm is stable with respect to noise, and present two 3D experiments which illustrate the efficiency and stability of our algorithm.

  1. How Do College Students Solve Logarithm Questions?

    Directory of Open Access Journals (Sweden)

    Tian Abdul Aziz

    2017-02-01

    Full Text Available The purpose of the study was to investigate college students’ work with logarithm questions. Qualitative descriptive research is chosen to reach the research goal. The participants of the study were fourteen Indonesian students who were enrolled at different universities in Ankara, Turkey. They worked to solve ten logarithm questions which were classified according to the contents. After analysing their written responses, interviews were conducted to obtain further explanation about their strategies and common mistakes. The study found that participants’ works in dealing with logarithm questions comprised of (a processing base, (b holding the rule, (c separating, (d jumping, and (e conditioning. Therewith, several participants made common mistake because of misconception about logarithm, arithmetical problems, and misuse of algebra concept. Implication of the finding of the study for teaching and learning logarithm were presented.

  2. Modeling and Solving the Train Pathing Problem

    Directory of Open Access Journals (Sweden)

    Chuen-Yih Chen

    2009-04-01

    Full Text Available In a railroad system, train pathing is concerned with the assignment of trains to links and tracks, and train timetabling allocates time slots to trains. In this paper, we present an optimization heuristic to solve the train pathing and timetabling problem. This heuristic allows the dwell time of trains in a station or link to be dependent on the assigned tracks. It also allows the minimum clearance time between the trains to depend on their relative status. The heuristic generates a number of alternative paths for each train service in the initialization phase. Then it uses a neighborhood search approach to find good feasible combinations of these paths. A linear program is developed to evaluate the quality of each combination that is encountered. Numerical examples are provided.

  3. Solving moment hierarchies for chemical reaction networks

    Science.gov (United States)

    Krishnamurthy, Supriya; Smith, Eric

    2017-10-01

    The study of chemical reaction networks (CRN’s) is a very active field. Earlier well-known results (Feinberg 1987 Chem. Enc. Sci. 42 2229, Anderson et al 2010 Bull. Math. Biol. 72 1947) identify a topological quantity called deficiency, for any CRN, which, when exactly equal to zero, leads to a unique factorized steady-state for these networks. No results exist however for the steady states of non-zero-deficiency networks. In this paper, we show how to write the full moment-hierarchy for any non-zero-deficiency CRN obeying mass-action kinetics, in terms of equations for the factorial moments. Using these, we can recursively predict values for lower moments from higher moments, reversing the procedure usually used to solve moment hierarchies. We show, for non-trivial examples, that in this manner we can predict any moment of interest, for CRN’s with non-zero deficiency and non-factorizable steady states.

  4. Teaching model of problem solving Programming Fundamentals

    Directory of Open Access Journals (Sweden)

    Iván Darwin Tutillo-Arcentales

    2016-10-01

    Full Text Available The formation process has been studied by several authors in those last years, although not always focusing in the technology careers which requires of a pedagogical and didactic point of view, which promotes behaviouring changes in the teachers with impact in the quality of graduates. The purposes of this paper is: to value the pedagogical fundamentals of the formation in the career Analysis of systems,in order to promote qualitative and quantitative improvements  in the students learning. The questioner applied to students and teachers proved the difficulties in the contents related to the algorithmic procedures, which constitutes a necessary content in their formation and to them contributes other syllabus of the first level. So it is necessary to model a theoretical construction which express the new relationships established from the psychological and didactic point of view in order to solving those situations from the programing.

  5. Solving Kepler's equation using implicit functions

    Science.gov (United States)

    Mortari, Daniele; Elipe, Antonio

    2014-01-01

    A new approach to solve Kepler's equation based on the use of implicit functions is proposed here. First, new upper and lower bounds are derived for two ranges of mean anomaly. These upper and lower bounds initialize a two-step procedure involving the solution of two implicit functions. These two implicit functions, which are non-rational (polynomial) Bézier functions, can be linear or quadratic, depending on the derivatives of the initial bound values. These are new initial bounds that have been compared and proven more accurate than Serafin's bounds. The procedure reaches machine error accuracy with no more that one quadratic and one linear iterations, experienced in the "tough range", where the eccentricity is close to one and the mean anomaly to zero. The proposed method is particularly suitable for space-based applications with limited computational capability.

  6. Solving a Deconvolution Problem in Photon Spectrometry

    CERN Document Server

    Aleksandrov, D; Hille, P T; Polichtchouk, B; Kharlov, Y; Sukhorukov, M; Wang, D; Shabratova, G; Demanov, V; Wang, Y; Tveter, T; Faltys, M; Mao, Y; Larsen, D T; Zaporozhets, S; Sibiryak, I; Lovhoiden, G; Potcheptsov, T; Kucheryaev, Y; Basmanov, V; Mares, J; Yanovsky, V; Qvigstad, H; Zenin, A; Nikolaev, S; Siemiarczuk, T; Yuan, X; Cai, X; Redlich, K; Pavlinov, A; Roehrich, D; Manko, V; Deloff, A; Ma, K; Maruyama, Y; Dobrowolski, T; Shigaki, K; Nikulin, S; Wan, R; Mizoguchi, K; Petrov, V; Mueller, H; Ippolitov, M; Liu, L; Sadovsky, S; Stolpovsky, P; Kurashvili, P; Nomokonov, P; Xu, C; Torii, H; Il'kaev, R; Zhang, X; Peresunko, D; Soloviev, A; Vodopyanov, A; Sugitate, T; Ullaland, K; Huang, M; Zhou, D; Nystrand, J; Punin, V; Yin, Z; Batyunya, B; Karadzhev, K; Nazarov, G; Fil'chagin, S; Nazarenko, S; Buskenes, J I; Horaguchi, T; Djuvsland, O; Chuman, F; Senko, V; Alme, J; Wilk, G; Fehlker, D; Vinogradov, Y; Budilov, V; Iwasaki, T; Ilkiv, I; Budnikov, D; Vinogradov, A; Kazantsev, A; Bogolyubsky, M; Lindal, S; Polak, K; Skaali, B; Mamonov, A; Kuryakin, A; Wikne, J; Skjerdal, K

    2010-01-01

    We solve numerically a deconvolution problem to extract the undisturbed spectrum from the measured distribution contaminated by the finite resolution of the measuring device. A problem of this kind emerges when one wants to infer the momentum distribution of the neutral pions by detecting the it decay photons using the photon spectrometer of the ALICE LHC experiment at CERN {[}1]. The underlying integral equation connecting the sought for pion spectrum and the measured gamma spectrum has been discretized and subsequently reduced to a system of linear algebraic equations. The latter system, however, is known to be ill-posed and must be regularized to obtain a stable solution. This task has been accomplished here by means of the Tikhonov regularization scheme combined with the L-curve method. The resulting pion spectrum is in an excellent quantitative agreement with the pion spectrum obtained from a Monte Carlo simulation. (C) 2010 Elsevier B.V. All rights reserved.

  7. MODELING AND SOLVING SELF-REFERENTIAL PUZZLES

    Directory of Open Access Journals (Sweden)

    Maja Bubalo

    2012-07-01

    Full Text Available The so-called self-referential puzzles are a very interesting kind of logic puzzles,aiming at developing the skill of logical thinking. A self-referential puzzle consists of asequence of questions about the puzzle itself. In this paper, we shall show some selfreferentialpuzzles, demonstrate how to model and solve them as propositional logicproblems, and how to mechanically generate new puzzles. For this, we shall make use ofthe specific advantages of Mozart/Oz system – the finite domain constraint programminglanguage and environment.We shall also show some new puzzles, according to our best knowledge not yet publishedelsewhere. The program in Mozart/Oz using our method generated these puzzles.

  8. Solving moment hierarchies for chemical reaction networks.

    Science.gov (United States)

    Krishnamurthy, Supriya; Smith, Eric

    2017-10-20

    The study of chemical reaction networks (CRN's) is a very active field. Earlier well-known results (Feinberg 1987 Chem. Enc. Sci . 42 2229, Anderson et al 2010 Bull. Math. Biol . 72 1947) identify a topological quantity called deficiency, for any CRN, which, when exactly equal to zero, leads to a unique factorized steady-state for these networks. No results exist however for the steady states of non-zero-deficiency networks. In this paper, we show how to write the full moment-hierarchy for any non-zero-deficiency CRN obeying mass-action kinetics, in terms of equations for the factorial moments. Using these, we can recursively predict values for lower moments from higher moments, reversing the procedure usually used to solve moment hierarchies. We show, for nontrivial examples, that in this manner we can predict any moment of interest, for CRN's with non-zero deficiency and non-factorizable steady states.

  9. Sleep promotes analogical transfer in problem solving.

    Science.gov (United States)

    Monaghan, Padraic; Sio, Ut Na; Lau, Sum Wai; Woo, Hoi Kei; Linkenauger, Sally A; Ormerod, Thomas C

    2015-10-01

    Analogical problem solving requires using a known solution from one problem to apply to a related problem. Sleep is known to have profound effects on memory and information restructuring, and so we tested whether sleep promoted such analogical transfer, determining whether improvement was due to subjective memory for problems, subjective recognition of similarity across related problems, or by abstract generalisation of structure. In Experiment 1, participants were exposed to a set of source problems. Then, after a 12-h period involving sleep or wake, they attempted target problems structurally related to the source problems but with different surface features. Experiment 2 controlled for time of day effects by testing participants either in the morning or the evening. Sleep improved analogical transfer, but effects were not due to improvements in subjective memory or similarity recognition, but rather effects of structural generalisation across problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Solving stochastic inflation for arbitrary potentials

    International Nuclear Information System (INIS)

    Martin, Jerome; Musso, Marcello

    2006-01-01

    A perturbative method for solving the Langevin equation of inflationary cosmology in the presence of backreaction is presented. In the Gaussian approximation, the method permits an explicit calculation of the probability distribution of the inflaton field for an arbitrary potential, with or without the volume effects taken into account. The perturbative method is then applied to various concrete models, namely, large field, small field, hybrid, and running mass inflation. New results on the stochastic behavior of the inflaton field in those models are obtained. In particular, it is confirmed that the stochastic effects can be important in new inflation while it is demonstrated they are negligible in (vacuum dominated) hybrid inflation. The case of stochastic running mass inflation is discussed in some details and it is argued that quantum effects blur the distinction between the four classical versions of this model. It is also shown that the self-reproducing regime is likely to be important in this case

  11. "I'm Not Very Good at Solving Problems": An Exploration of Students' Problem Solving Behaviours

    Science.gov (United States)

    Muir, Tracey; Beswick, Kim; Williamson, John

    2008-01-01

    This paper reports one aspect of a larger study which looked at the strategies used by a selection of grade 6 students to solve six non-routine mathematical problems. The data revealed that the students exhibited many of the behaviours identified in the literature as being associated with novice and expert problem solvers. However, the categories…

  12. How to make university students solve physics problems requiring mathematical skills: The "Adventurous Problem Solving" approach

    NARCIS (Netherlands)

    de Mul, F.F.M.; Martin Batlle, C.; Martin i Batlle, Cristina; de Bruijn, Imme; Rinzema, K.; Rinzema, Kees

    2003-01-01

    Teaching physics to first-year university students (in the USA: junior/senior level) is often hampered by their lack of skills in the underlying mathematics, and that in turn may block their understanding of the physics and their ability to solve problems. Examples are vector algebra, differential

  13. A hybrid algorithm for solving inverse problems in elasticity

    Directory of Open Access Journals (Sweden)

    Barabasz Barbara

    2014-12-01

    Full Text Available The paper offers a new approach to handling difficult parametric inverse problems in elasticity and thermo-elasticity, formulated as global optimization ones. The proposed strategy is composed of two phases. In the first, global phase, the stochastic hp-HGS algorithm recognizes the basins of attraction of various objective minima. In the second phase, the local objective minimizers are closer approached by steepest descent processes executed singly in each basin of attraction. The proposed complex strategy is especially dedicated to ill-posed problems with multimodal objective functionals. The strategy offers comparatively low computational and memory costs resulting from a double-adaptive technique in both forward and inverse problem domains. We provide a result on the Lipschitz continuity of the objective functional composed of the elastic energy and the boundary displacement misfits with respect to the unknown constitutive parameters. It allows common scaling of the accuracy of solving forward and inverse problems, which is the core of the introduced double-adaptive technique. The capability of the proposed method of finding multiple solutions is illustrated by a computational example which consists in restoring all feasible Young modulus distributions minimizing an objective functional in a 3D domain of a photo polymer template obtained during step and flash imprint lithography.

  14. Solving Math Problems Approximately: A Developmental Perspective.

    Directory of Open Access Journals (Sweden)

    Dana Ganor-Stern

    Full Text Available Although solving arithmetic problems approximately is an important skill in everyday life, little is known about the development of this skill. Past research has shown that when children are asked to solve multi-digit multiplication problems approximately, they provide estimates that are often very far from the exact answer. This is unfortunate as computation estimation is needed in many circumstances in daily life. The present study examined 4th graders, 6th graders and adults' ability to estimate the results of arithmetic problems relative to a reference number. A developmental pattern was observed in accuracy, speed and strategy use. With age there was a general increase in speed, and an increase in accuracy mainly for trials in which the reference number was close to the exact answer. The children tended to use the sense of magnitude strategy, which does not involve any calculation but relies mainly on an intuitive coarse sense of magnitude, while the adults used the approximated calculation strategy which involves rounding and multiplication procedures, and relies to a greater extent on calculation skills and working memory resources. Importantly, the children were less accurate than the adults, but were well above chance level. In all age groups performance was enhanced when the reference number was smaller (vs. larger than the exact answer and when it was far (vs. close from it, suggesting the involvement of an approximate number system. The results suggest the existence of an intuitive sense of magnitude for the results of arithmetic problems that might help children and even adults with difficulties in math. The present findings are discussed in the context of past research reporting poor estimation skills among children, and the conditions that might allow using children estimation skills in an effective manner.

  15. Solving Math Problems Approximately: A Developmental Perspective.

    Science.gov (United States)

    Ganor-Stern, Dana

    2016-01-01

    Although solving arithmetic problems approximately is an important skill in everyday life, little is known about the development of this skill. Past research has shown that when children are asked to solve multi-digit multiplication problems approximately, they provide estimates that are often very far from the exact answer. This is unfortunate as computation estimation is needed in many circumstances in daily life. The present study examined 4th graders, 6th graders and adults' ability to estimate the results of arithmetic problems relative to a reference number. A developmental pattern was observed in accuracy, speed and strategy use. With age there was a general increase in speed, and an increase in accuracy mainly for trials in which the reference number was close to the exact answer. The children tended to use the sense of magnitude strategy, which does not involve any calculation but relies mainly on an intuitive coarse sense of magnitude, while the adults used the approximated calculation strategy which involves rounding and multiplication procedures, and relies to a greater extent on calculation skills and working memory resources. Importantly, the children were less accurate than the adults, but were well above chance level. In all age groups performance was enhanced when the reference number was smaller (vs. larger) than the exact answer and when it was far (vs. close) from it, suggesting the involvement of an approximate number system. The results suggest the existence of an intuitive sense of magnitude for the results of arithmetic problems that might help children and even adults with difficulties in math. The present findings are discussed in the context of past research reporting poor estimation skills among children, and the conditions that might allow using children estimation skills in an effective manner.

  16. A Faster Algorithm for Solving One-Clock Priced Timed Games

    DEFF Research Database (Denmark)

    Hansen, Thomas Dueholm; Ibsen-Jensen, Rasmus; Miltersen, Peter Bro

    2012-01-01

    previously known time bound for solving one-clock priced timed games was 2^(O(n^2+m)), due to Rutkowski. For our improvement, we introduce and study a new algorithm for solving one-clock priced timed games, based on the sweep-line technique from computational geometry and the strategy iteration paradigm from......One-clock priced timed games is a class of two-player, zero-sum, continuous-time games that was defined and thoroughly studied in previous works. We show that one-clock priced timed games can be solved in time m 12^n n^(O(1)), where n is the number of states and m is the number of actions. The best...

  17. A Faster Algorithm for Solving One-Clock Priced Timed Games

    DEFF Research Database (Denmark)

    Hansen, Thomas Dueholm; Ibsen-Jensen, Rasmus; Miltersen, Peter Bro

    2013-01-01

    previously known time bound for solving one-clock priced timed games was 2O(n2+m) , due to Rutkowski. For our improvement, we introduce and study a new algorithm for solving one-clock priced timed games, based on the sweep-line technique from computational geometry and the strategy iteration paradigm from......One-clock priced timed games is a class of two-player, zero-sum, continuous-time games that was defined and thoroughly studied in previous works. We show that one-clock priced timed games can be solved in time m 12 n n O(1), where n is the number of states and m is the number of actions. The best...

  18. Excel 2016 for biological and life sciences statistics a guide to solving practical problems

    CERN Document Server

    Quirk, Thomas J; Horton, Howard F

    2016-01-01

    This book is a step-by-step exercise-driven guide for students and practitioners who need to master Excel to solve practical biological and life science problems. If understanding statistics isn’t your strongest suit, you are not especially mathematically-inclined, or if you are wary of computers, this is the right book for you. Excel is an effective learning tool for quantitative analyses in biological and life sciences courses. Its powerful computational ability and graphical functions make learning statistics much easier than in years past. However, Excel 2016 for Biological and Life Sciences Statistics: A Guide to Solving Practical Problems is the first book to capitalize on these improvements by teaching students and managers how to apply Excel 2016 to statistical techniques necessary in their courses and work. Each chapter explains statistical formulas and directs the reader to use Excel commands to solve specific, easy-to-understand biological and life science problems. Practice problems are provided...

  19. Solving large-scale sparse eigenvalue problems and linear systems of equations for accelerator modeling

    Energy Technology Data Exchange (ETDEWEB)

    Gene Golub; Kwok Ko

    2009-03-30

    The solutions of sparse eigenvalue problems and linear systems constitute one of the key computational kernels in the discretization of partial differential equations for the modeling of linear accelerators. The computational challenges faced by existing techniques for solving those sparse eigenvalue problems and linear systems call for continuing research to improve on the algorithms so that ever increasing problem size as required by the physics application can be tackled. Under the support of this award, the filter algorithm for solving large sparse eigenvalue problems was developed at Stanford to address the computational difficulties in the previous methods with the goal to enable accelerator simulations on then the world largest unclassified supercomputer at NERSC for this class of problems. Specifically, a new method, the Hemitian skew-Hemitian splitting method, was proposed and researched as an improved method for solving linear systems with non-Hermitian positive definite and semidefinite matrices.

  20. Excel 2016 for environmental sciences statistics a guide to solving practical problems

    CERN Document Server

    Quirk, Thomas J; Horton, Howard F

    2016-01-01

    This book is a step-by-step exercise-driven guide for students and practitioners who need to master Excel to solve practical environmental science problems. If understanding statistics isn’t your strongest suit, you are not especially mathematically-inclined, or if you are wary of computers, this is the right book for you. Excel is an effective learning tool for quantitative analyses in environmental science courses. Its powerful computational ability and graphical functions make learning statistics much easier than in years past. However, Excel 2016 for Environmental Science Statistics: A Guide to Solving Practical Problems is the first book to capitalize on these improvements by teaching students and managers how to apply Excel 2016 to statistical techniques necessary in their courses and work. Each chapter explains statistical formulas and directs the reader to use Excel commands to solve specific, easy-to-understand environmental science problems. Practice problems are provided at the end of each chapte...

  1. Excel 2016 for physical sciences statistics a guide to solving practical problems

    CERN Document Server

    Quirk, Thomas J; Horton, Howard F

    2016-01-01

    This book is a step-by-step exercise-driven guide for students and practitioners who need to master Excel to solve practical physical science problems. If understanding statistics isn’t your strongest suit, you are not especially mathematically-inclined, or if you are wary of computers, this is the right book for you. Excel is an effective learning tool for quantitative analyses in environmental science courses. Its powerful computational ability and graphical functions make learning statistics much easier than in years past. However, Excel 2016 for Physical Sciences Statistics: A Guide to Solving Practical Problems is the first book to capitalize on these improvements by teaching students and managers how to apply Excel 2016 to statistical techniques necessary in their courses and work. Each chapter explains statistical formulas and directs the reader to use Excel commands to solve specific, easy-to-understand physical science problems. Practice problems are provided at the end of each chapter with their s...

  2. Review on solving the inverse problem in EEG source analysis

    Directory of Open Access Journals (Sweden)

    Fabri Simon G

    2008-11-01

    Full Text Available Abstract In this primer, we give a review of the inverse problem for EEG source localization. This is intended for the researchers new in the field to get insight in the state-of-the-art techniques used to find approximate solutions of the brain sources giving rise to a scalp potential recording. Furthermore, a review of the performance results of the different techniques is provided to compare these different inverse solutions. The authors also include the results of a Monte-Carlo analysis which they performed to compare four non parametric algorithms and hence contribute to what is presently recorded in the literature. An extensive list of references to the work of other researchers is also provided. This paper starts off with a mathematical description of the inverse problem and proceeds to discuss the two main categories of methods which were developed to solve the EEG inverse problem, mainly the non parametric and parametric methods. The main difference between the two is to whether a fixed number of dipoles is assumed a priori or not. Various techniques falling within these categories are described including minimum norm estimates and their generalizations, LORETA, sLORETA, VARETA, S-MAP, ST-MAP, Backus-Gilbert, LAURA, Shrinking LORETA FOCUSS (SLF, SSLOFO and ALF for non parametric methods and beamforming techniques, BESA, subspace techniques such as MUSIC and methods derived from it, FINES, simulated annealing and computational intelligence algorithms for parametric methods. From a review of the performance of these techniques as documented in the literature, one could conclude that in most cases the LORETA solution gives satisfactory results. In situations involving clusters of dipoles, higher resolution algorithms such as MUSIC or FINES are however preferred. Imposing reliable biophysical and psychological constraints, as done by LAURA has given superior results. The Monte-Carlo analysis performed, comparing WMN, LORETA, sLORETA and SLF

  3. 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

  4. The Effects of GO Solve Word Problems Math Intervention on Applied Problem Solving Skills of Low Performing Fifth Grade Students

    Science.gov (United States)

    Fede, Jessica L.

    2010-01-01

    This research investigation examined the effects of "GO Solve Word Problems" math intervention on problem-solving skills of struggling 5th grade students. In a randomized controlled study, 16 5th grade students were given a 12-week intervention of "GO Solve", a computer-based program designed to teach schema-based instruction…

  5. Acquired Techniques

    DEFF Research Database (Denmark)

    Lunde Nielsen, Espen; Halse, Karianne

    2013-01-01

    Acquired Techniques - a Leap into the Archive, at Aarhus School of Architecture. In collaboration with Karianne Halse, James Martin and Mika K. Friis. Following the footsteps of past travelers this is a journey into tools and techniques of the architectural process. The workshop will focus upon...

  6. Improving mathematical problem solving skills through visual media

    Science.gov (United States)

    Widodo, S. A.; Darhim; Ikhwanudin, T.

    2018-01-01

    The purpose of this article was to find out the enhancement of students’ mathematical problem solving by using visual learning media. The ability to solve mathematical problems is the ability possessed by students to solve problems encountered, one of the problem-solving model of Polya. This preliminary study was not to make a model, but it only took a conceptual approach by comparing the various literature of problem-solving skills by linking visual learning media. The results of the study indicated that the use of learning media had not been appropriated so that the ability to solve mathematical problems was not optimal. The inappropriateness of media use was due to the instructional media that was not adapted to the characteristics of the learners. Suggestions that can be given is the need to develop visual media to increase the ability to solve problems.

  7. Flexibility in Mathematics Problem Solving Based on Adversity Quotient

    Science.gov (United States)

    Dina, N. A.; Amin, S. M.; Masriyah

    2018-01-01

    Flexibility is an ability which is needed in problem solving. One of the ways in problem solving is influenced by Adversity Quotient (AQ). AQ is the power of facing difficulties. There are three categories of AQ namely climber, camper, and quitter. This research is a descriptive research using qualitative approach. The aim of this research is to describe flexibility in mathematics problem solving based on Adversity Quotient. The subjects of this research are climber student, camper student, and quitter student. This research was started by giving Adversity Response Profile (ARP) questioner continued by giving problem solving task and interviews. The validity of data measurement was using time triangulation. The results of this research shows that climber student uses two strategies in solving problem and doesn’t have difficulty. The camper student uses two strategies in solving problem but has difficulty to finish the second strategies. The quitter student uses one strategy in solving problem and has difficulty to finish it.

  8. The Elementary School Students’ Mathematical Problem Solving Based on Reading Abilities

    Science.gov (United States)

    Wulandari, R. D.; Lukito, A.; Khabibah, S.

    2018-01-01

    The aim of this research is to describe the third grade of elementary school students’ mathematical problem in solving skills based on their reading abilities. This research is a descriptive research with qualitative approach. This research was conducted at elementary school Kebraon II Surabaya in second semester of 2016-2017 academic years. The participants of this research consist of third grade students with different reading abilities that are independent level, instructional level and frustration level. The participants of this research were selected with purposive sampling technique. The data of this study were collected using reading the narration texts, the Ekwall and Shanker Informal Reading Inventory, problem solving task and interview guidelines. The collected data were evaluated using a descriptive analysis method. Once the study had been completed, it was concluded that problem solving skills varied according to reading abilities, student with independent level and instructional level can solve the problem and students with frustration level can’t solve the problem because they can’t interpret the problem well.

  9. APPLICATION OF THE PERFORMANCE SELECTION INDEX METHOD FOR SOLVING MACHINING MCDM PROBLEMS

    Directory of Open Access Journals (Sweden)

    Dušan Petković

    2017-04-01

    Full Text Available Complex nature of machining processes requires the use of different methods and techniques for process optimization. Over the past few years a number of different optimization methods have been proposed for solving continuous machining optimization problems. In manufacturing environment, engineers are also facing a number of discrete machining optimization problems. In order to help decision makers in solving this type of optimization problems a number of multi criteria decision making (MCDM methods have been proposed. This paper introduces the use of an almost unexplored MCDM method, i.e. performance selection index (PSI method for solving machining MCDM problems. The main motivation for using the PSI method is that it is not necessary to determine criteria weights as in other MCDM methods. Applicability and effectiveness of the PSI method have been demonstrated while solving two case studies dealing with machinability of materials and selection of the most suitable cutting fluid for the given machining application. The obtained rankings have good correlation with those derived by the past researchers using other MCDM methods which validate the usefulness of this method for solving machining MCDM problems.

  10. Directed Bee Colony Optimization Algorithm to Solve the Nurse Rostering Problem.

    Science.gov (United States)

    Rajeswari, M; Amudhavel, J; Pothula, Sujatha; Dhavachelvan, P

    2017-01-01

    The Nurse Rostering Problem is an NP-hard combinatorial optimization, scheduling problem for assigning a set of nurses to shifts per day by considering both hard and soft constraints. A novel metaheuristic technique is required for solving Nurse Rostering Problem (NRP). This work proposes a metaheuristic technique called Directed Bee Colony Optimization Algorithm using the Modified Nelder-Mead Method for solving the NRP. To solve the NRP, the authors used a multiobjective mathematical programming model and proposed a methodology for the adaptation of a Multiobjective Directed Bee Colony Optimization (MODBCO). MODBCO is used successfully for solving the multiobjective problem of optimizing the scheduling problems. This MODBCO is an integration of deterministic local search, multiagent particle system environment, and honey bee decision-making process. The performance of the algorithm is assessed using the standard dataset INRC2010, and it reflects many real-world cases which vary in size and complexity. The experimental analysis uses statistical tools to show the uniqueness of the algorithm on assessment criteria.

  11. Problem-Solving Test: Restriction Endonuclease Mapping

    Science.gov (United States)

    Szeberenyi, Jozsef

    2011-01-01

    The term "restriction endonuclease mapping" covers a number of related techniques used to identify specific restriction enzyme recognition sites on small DNA molecules. A method for restriction endonuclease mapping of a 1,000-basepair (bp)-long DNA molecule is described in the fictitious experiment of this test. The most important fact needed to…

  12. Combined Approach for Solving the Electromagnetic Induction ...

    African Journals Online (AJOL)

    Inverse electromagnetic induction is an imaging technique for reconstructing the conductivity and permeability distributions in a region of interest from measurements of impedance made at its boundary. In general, there are two approaches to the reconstruction problem: the pixel-based approach and the parameter-based ...

  13. Professional Development: How Young Children Solve Problems

    Science.gov (United States)

    Shure, Myrna B.

    2006-01-01

    There are lots of ways to handle behavior problems in the classroom. Some teachers send difficult children to time out, others tell them what and what not to do, and many explain why. But these techniques have one thing in common: they all do the thinking for the child. In this article, the author discusses how to help children handle conflicts…

  14. Generating and Solving Symbolic Parity Games

    Directory of Open Access Journals (Sweden)

    Gijs Kant

    2014-07-01

    Full Text Available We present a new tool for verification of modal mu-calculus formulae for process specifications, based on symbolic parity games. It enhances an existing method, that first encodes the problem to a Parameterised Boolean Equation System (PBES and then instantiates the PBES to a parity game. We improved the translation from specification to PBES to preserve the structure of the specification in the PBES, we extended LTSmin to instantiate PBESs to symbolic parity games, and implemented the recursive parity game solving algorithm by Zielonka for symbolic parity games. We use Multi-valued Decision Diagrams (MDDs to represent sets and relations, thus enabling the tools to deal with very large systems. The transition relation is partitioned based on the structure of the specification, which allows for efficient manipulation of the MDDs. We performed two case studies on modular specifications, that demonstrate that the new method has better time and memory performance than existing PBES based tools and can be faster (but slightly less memory efficient than the symbolic model checker NuSMV.

  15. Solved? The reductive radiation chemistry of alanine.

    Science.gov (United States)

    Pauwels, Ewald; De Cooman, Hendrik; Waroquier, Michel; Hole, Eli O; Sagstuen, Einar

    2014-02-14

    The structural changes throughout the entire reductive radiation-induced pathway of l-α-alanine are solved on an atomistic level with the aid of periodic DFT and nudged elastic band (NEB) simulations. This yields unprecedented information on the conformational changes taking place, including the protonation state of the carboxyl group in the "unstable" and "stable" alanine radicals and the internal transformation converting these two radical variants at temperatures above 220 K. The structures of all stable radicals were verified by calculating EPR properties and comparing those with experimental data. The variation of the energy throughout the full radiochemical process provides crucial insight into the reason why these structural changes and rearrangements occur. Starting from electron capture, the excess electron quickly localizes on the carbon of a carboxyl group, which pyramidalizes and receives a proton from the amino group of a neighboring alanine molecule, forming a first stable radical species (up to 150 K). In the temperature interval 150-220 K, this radical deaminates and deprotonates at the carboxyl group, the detached amino group undergoes inversion and its methyl group sustains an internal rotation. This yields the so-called "unstable alanine radical". Above 220 K, triggered by the attachment of an additional proton on the detached amino group, the radical then undergoes an internal rotation in the reverse direction, giving rise to the "stable alanine radical", which is the final stage in the reductive radiation-induced decay of alanine.

  16. Solved Problems in Quantum and Statistical Mechanics

    CERN Document Server

    Cini, Michele; Sbragaglia, Mauro

    2012-01-01

    This work arises from our teaching this subject during many years. The vast majority of these exercises are the exams we gave to our students in this period. We carefully selected the subjects of the exercises to cover all the material which is most needed  and which is treated in the most well known texts on these subjects. Each exercise is carefully solved in full details, explaining the theory behind the solution with particular care for those issues that, from our experience, are found most difficult from the average student. Indeed, several exercises are designed to throw light on  aspects of the theory that, for one reason or another, are usually neglected with the result to make the students feel uneasy about them. In fact most students get acquainted just with the more common manipulations,  which are illustrated by  many examples in textbooks. Our exercises never require extensive calculations  but tend to be somewhat unusual  and force the solver  to think about the problem starting from the ...

  17. Problem-solving in a Constructivist Environment

    Directory of Open Access Journals (Sweden)

    Lee Chien Sing

    1999-01-01

    Full Text Available The dynamic challenges of an increasingly borderless world buoyed by advances in telecommunications and information technology has resulted in educational reform and subsequently, a reconceptualisation of what constitutes a learner, learning and the influence of the learning environment on the process of learning. In keeping up with the changing trends and challenges of an increasingly networked, dynamic and challenging international community, means to provide an alternative environment that stimulates inquiry and equips learners with the skills needed to manage technological change and innovations must be considered. This paper discusses the importance of interaction, cognition and context, collaboration in a networked computer-mediated environment, the problem-solving approach as a catalyst in stimulating creative and critical thinking and in providing context for meaningful interaction and whether the interactive environment created through computer-mediated collaboration will motivate learners to be responsible for their own learning and be independent thinkers. The sample involved learners from three schools in three different countries. Findings conclude that a rich interactive environment must be personally relevant to the learner by simulating authentic problems without lowering the degree of cognitive complexity. Review in curriculum, assessment and teacher training around constructivist principles are also imperative as these interrelated factors form part of the learning process system.

  18. Solve the Dilemma of Over-Simplification

    Science.gov (United States)

    Schmitt, Gerhard

    Complexity science can help to understand the functioning and the interaction of the components of a city. In 1965, Christopher Alexander gave in his book A city is not a tree a description of the complex nature of urban organization. At this time, neither high-speed computers nor urban big data existed. Today, Luis Bettencourt et al. use complexity science to analyze data for countries, regions, or cities. The results can be used globally in other cities. Objectives of complexity science with regard to future cities are the observation and identification of tendencies and regularities in behavioral patterns, and to find correlations between them and spatial configurations. Complex urban systems cannot be understood in total yet. But research focuses on describing the system by finding some simple, preferably general and emerging patterns and rules that can be used for urban planning. It is important that the influencing factors are not just geo-spatial patterns but also consider variables which are important for the design quality. Complexity science is a way to solve the dilemma of oversimplification of insights from existing cities and their applications to new cities. An example: The effects of streets, public places and city structures on citizens and their behavior depend on how they are perceived. To describe this perception, it is not sufficient to consider only particular characteristics of the urban environment. Different aspects play a role and influence each other. Complexity science could take this fact into consideration and handle the non-linearity of the system...

  19. Solving the Examination Timetabling Problem in GPUs

    Directory of Open Access Journals (Sweden)

    Vasileios Kolonias

    2014-07-01

    Full Text Available The examination timetabling problem belongs to the class of combinatorial optimization problems and is of great importance for every University. In this paper, a hybrid evolutionary algorithm running on a GPU is employed to solve the examination timetabling problem. The hybrid evolutionary algorithm proposed has a genetic algorithm component and a greedy steepest descent component. The GPU computational capabilities allow the use of very large population sizes, leading to a more thorough exploration of the problem solution space. The GPU implementation, depending on the size of the problem, is up to twenty six times faster than the identical single-threaded CPU implementation of the algorithm. The algorithm is evaluated with the well known Toronto datasets and compares well with the best results found in the bibliography. Moreover, the selection of the encoding of the chromosomes and the tournament selection size as the population grows are examined and optimized. The compressed sparse row format is used for the conflict matrix and was proven essential to the process, since most of the datasets have a small conflict density, which translates into an extremely sparse matrix.

  20. Can Architecture Design Solve Social Problem?

    Science.gov (United States)

    Ginting, S. W.; TSB Darjosanjoto, E.; Sulistyarso, H.

    2017-03-01

    Most of architects and urban designers believe physical design gives impact on our social life. For example, a sign or landmark in the middle of a city makes people find orientation easier. In vice verse, most of social scientists believe it is social dynamic that plays role in shaping our space. How people spend their time moving from real space into cyber space is a proof that life style and IT give impact to space usage. This paper argues that interaction between physical design and social change is a two ways process. Both design aspect and social dynamic influence each other. This paper aims to examine how designing of gated community plays important role in increasing or decreasing segregation, both spatially and socially. The paper explores some architectural design principles applied in a gated community called CitraLand in west Surabaya, Indonesia, and addresses segregation between CitraLanders and outside kampung. We find CitraLand is designed openly and fully accessible for outsiders. It provides public spaces and several accessible gates and streets without walls and fences making all places inside and outside CitraLand spatially integrated. What’s interesting is it still reinforces social segregation due to its policy on prohibiting using the public park. We believe CitraLand’s planning and designing has successfully solved segregation problem spatially not socially.

  1. Intensity techniques

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    2008-01-01

    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....

  2. Rejection Sensitivity and Depression: Indirect Effects Through Problem Solving.

    Science.gov (United States)

    Kraines, Morganne A; Wells, Tony T

    2017-01-01

    Rejection sensitivity (RS) and deficits in social problem solving are risk factors for depression. Despite their relationship to depression and the potential connection between them, no studies have examined RS and social problem solving together in the context of depression. As such, we examined RS, five facets of social problem solving, and symptoms of depression in a young adult sample. A total of 180 participants completed measures of RS, social problem solving, and depressive symptoms. We used bootstrapping to examine the indirect effect of RS on depressive symptoms through problem solving. RS was positively associated with depressive symptoms. A negative problem orientation, impulsive/careless style, and avoidance style of social problem solving were positively associated with depressive symptoms, and a positive problem orientation was negatively associated with depressive symptoms. RS demonstrated an indirect effect on depressive symptoms through two social problem-solving facets: the tendency to view problems as threats to one's well-being and an avoidance problem-solving style characterized by procrastination, passivity, or overdependence on others. These results are consistent with prior research that found a positive association between RS and depression symptoms, but this is the first study to implicate specific problem-solving deficits in the relationship between RS and depression. Our results suggest that depressive symptoms in high RS individuals may result from viewing problems as threats and taking an avoidant, rather than proactive, approach to dealing with problems. These findings may have implications for problem-solving interventions for rejection sensitive individuals.

  3. Methodological evolutions in human-machine cooperative problem solving with applications to nuclear plants

    International Nuclear Information System (INIS)

    Kitamura, Masaharu; Takahashi, Makoto

    2002-01-01

    A new framework for attaining higher safety of nuclear plants through introducing machine intelligence and robots has been proposed in this paper. The main emphasis of the framework is placed on user-centered human-machine cooperation in solving problems experienced during conducting operation, monitoring and maintenance activities in nuclear plants. In this framework, human operator is supposed to take initiative of actions at any moment of operation. No attempt has been made to replace human experts by machine intelligence and robots. Efforts have been paid to clarify the expertise and behavioral model of human experts so that the developed techniques are consistent with human mental activities in solving highly complicated operational and maintenance problems. Several techniques essential to the functioning of the framework have also been introduced. Modification of environment to provide support information has also been pursued to realize the concept of ubiquitous computing. (author)

  4. Blackboard system generator (BSG) - An alternative distributed problem-solving paradigm

    Science.gov (United States)

    Silverman, Barry G.; Feggos, Kostas; Chang, Joseph Shih

    1989-01-01

    A status review is presented for a generic blackboard-based distributed problem-solving environment in which multiple-agent cooperation can be effected. This environment is organized into a shared information panel, a chairman control panel, and a metaplanning panel. Each panel contains a number of embedded AI techniques that facilitate its operation and that provide heuristics for solving the underlying team-agent decision problem. The status of these panels and heuristics is described along with a number of robustness considerations. The techniques for each of the three panels and for four sets of paradigm-related advances are described, along with selected results from classroom teaching experiments and from three applications.

  5. Assistência ao familiar cuidador em convívio com o alcoolista, por meio da técnica de solução de problemas Atención al familiar-cuidador que convive con alcohólico, a través de la técnica de solución de problemas Care for family caregivers living with alcoholics through the problem solving technique

    Directory of Open Access Journals (Sweden)

    Jurema Ribeiro Luiz Gonçalves

    2010-06-01

    Full Text Available Esta pesquisa teve como objetivo oferecer treinamento aos familiares cuidadores de pacientes alcoolistas, por meio da técnica de solução de problemas. Trata-se de estudo descritivo, do qual participaram 8 familiares cuidadores. Realizaram-se três reuniões nas quais foram trabalhados temas como alterações do comportamento e esgotamento de quem cuida. Desses encontros, emergiram sentimentos que a situação alterações do comportamento mobiliza, autocuidado do cuidador através do compartilhamento das responsabilidades com familiares e outros e busca por atendimento especializado. Os participantes do estudo consideraram positiva a intervenção proposta, pois possibilitou a reflexão acerca de suas vivências e o seu potencial para manejar dificuldades. Acredita-se, aqui, que esse seja um horizonte a ser trilhado pelo enfermeiro, munido de capacitação para prestar assistência ao familiar cuidador.La finalidad de esta investigación fue ofrecer capacitación a los familiares que cuidan de pacientes alcohólicos a través de la técnica de solución de problemas. Se trata de un estudio descriptivo, en el cual participaron 8 familiares-cuidadores. Se realizaron 3 reuniones, donde fueron abordados temas como: alteraciones del comportamiento y agotamiento de quien cuida. De esos encuentros emergieron sentimientos provenientes de la situación de alteraciones de comportamiento, como: autocuidado del cuidador a través de compartir las responsabilidades con familiares y otros y, la búsqueda de atención especializada. Los participantes del estudio consideraron positiva la intervención propuesta, pues posibilitó la reflexión acerca de sus vivencias y mostró su potencial para manejar dificultades. Creemos que este sea un camino a ser seguido por el enfermero capacitado para prestar atención al familiar-cuidador.The aim of this study was to offer training to family caregivers of alcoholic patients through the problem solving technique. This

  6. Application of differential transformation method for solving dengue transmission mathematical model

    Science.gov (United States)

    Ndii, Meksianis Z.; Anggriani, Nursanti; Supriatna, Asep K.

    2018-03-01

    The differential transformation method (DTM) is a semi-analytical numerical technique which depends on Taylor series and has application in many areas including Biomathematics. The aim of this paper is to employ the differential transformation method (DTM) to solve system of non-linear differential equations for dengue transmission mathematical model. Analytical and numerical solutions are determined and the results are compared to that of Runge-Kutta method. We found a good agreement between DTM and Runge-Kutta method.

  7. A semi-analytical approach for solving of nonlinear systems of functional differential equations with delay

    Science.gov (United States)

    Rebenda, Josef; Šmarda, Zdeněk

    2017-07-01

    In the paper, we propose a correct and efficient semi-analytical approach to solve initial value problem for systems of functional differential equations with delay. The idea is to combine the method of steps and differential transformation method (DTM). In the latter, formulas for proportional arguments and nonlinear terms are used. An example of using this technique for a system with constant and proportional delays is presented.

  8. Application of the Artificial Bee Colony Algorithm for Solving the Set Covering Problem

    OpenAIRE

    Crawford, Broderick; Soto, Ricardo; Cuesta, Rodrigo; Paredes, Fernando

    2014-01-01

    The set covering problem is a formal model for many practical optimization problems. In the set covering problem the goal is to choose a subset of the columns of minimal cost that covers every row. Here, we present a novel application of the artificial bee colony algorithm to solve the non-unicost set covering problem. The artificial bee colony algorithm is a recent swarm metaheuristic technique based on the intelligent foraging behavior of honey bees. Experimental results show...

  9. Computer architecture for solving consistent labeling problems

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, J.R.; Haralick, R.M.; Shapiro, L.G.

    1982-01-01

    Consistent labeling problems are a family of np-complete constraint satisfaction problems such as school timetabling, for which a conventional computer may be too slow. There are a variety of techniques for reducing the elapsed time to find one or all solutions to a consistent labeling problem. The paper discusses and illustrates solutions consisting of special hardware to accomplish the required constraint propagation and an asynchronous network of intercommunicating computers to accomplish the tree search in parallel. 5 references.

  10. Forward problem of electrocardiography: is it solved?

    Science.gov (United States)

    Bear, Laura R; Cheng, Leo K; LeGrice, Ian J; Sands, Gregory B; Lever, Nigel A; Paterson, David J; Smaill, Bruce H

    2015-06-01

    The relationship between epicardial and body surface potentials defines the forward problem of electrocardiography. A robust formulation of the forward problem is instrumental to solving the inverse problem, in which epicardial potentials are computed from known body surface potentials. Here, the accuracy of different forward models has been evaluated experimentally. Body surface and epicardial potentials were recorded simultaneously in anesthetized closed-chest pigs (n=5) during sinus rhythm, and epicardial and endocardial ventricular pacing (65 records in total). Body surface potentials were simulated from epicardial recordings using experiment-specific volume conductor models constructed from magnetic resonance imaging. Results for homogeneous (isotropic electric properties) and inhomogeneous (incorporating lungs, anisotropic skeletal muscle, and subcutaneous fat) forward models were compared with measured body surface potentials. Correlation coefficients were 0.85±0.08 across all animals and activation sequences with no significant difference between homogeneous and inhomogeneous solutions (P=0.85). Despite this, there was considerable variance between simulated and measured body surface potential distributions. Differences between the body surface potential extrema predicted with homogeneous forward models were 55% to 78% greater than observed (P<0.05) and attenuation of potentials adjacent to extrema were 10% to 171% greater (P<0.03). The length and orientation of the vector between potential extrema were also significantly different. Inclusion of inhomogeneous electric properties in the forward model reduced, but did not eliminate these differences. These results demonstrate that homogeneous volume conductor models introduce substantial spatial inaccuracies in forward problem solutions. This probably affects the precision of inverse reconstructions of cardiac potentials, in which this assumption is made. © 2015 American Heart Association, Inc.

  11. The semantic system is involved in mathematical problem solving.

    Science.gov (United States)

    Zhou, Xinlin; Li, Mengyi; Li, Leinian; Zhang, Yiyun; Cui, Jiaxin; Liu, Jie; Chen, Chuansheng

    2018-02-01

    Numerous studies have shown that the brain regions around bilateral intraparietal cortex are critical for number processing and arithmetical computation. However, the neural circuits for more advanced mathematics such as mathematical problem solving (with little routine arithmetical computation) remain unclear. Using functional magnetic resonance imaging (fMRI), this study (N = 24 undergraduate students) compared neural bases of mathematical problem solving (i.e., number series completion, mathematical word problem solving, and geometric problem solving) and arithmetical computation. Direct subject- and item-wise comparisons revealed that mathematical problem solving typically had greater activation than arithmetical computation in all 7 regions of the semantic system (which was based on a meta-analysis of 120 functional neuroimaging studies on semantic processing). Arithmetical computation typically had greater activation in the supplementary motor area and left precentral gyrus. The results suggest that the semantic system in the brain supports mathematical problem solving. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. The effects of monitoring environment on problem-solving performance.

    Science.gov (United States)

    Laird, Brian K; Bailey, Charles D; Hester, Kim

    2018-01-01

    While effective and efficient solving of everyday problems is important in business domains, little is known about the effects of workplace monitoring on problem-solving performance. In a laboratory experiment, we explored the monitoring environment's effects on an individual's propensity to (1) establish pattern solutions to problems, (2) recognize when pattern solutions are no longer efficient, and (3) solve complex problems. Under three work monitoring regimes-no monitoring, human monitoring, and electronic monitoring-114 participants solved puzzles for monetary rewards. Based on research related to worker autonomy and theory of social facilitation, we hypothesized that monitored (versus non-monitored) participants would (1) have more difficulty finding a pattern solution, (2) more often fail to recognize when the pattern solution is no longer efficient, and (3) solve fewer complex problems. Our results support the first two hypotheses, but in complex problem solving, an interaction was found between self-assessed ability and the monitoring environment.

  13. Social problem-solving in Chinese baccalaureate nursing students.

    Science.gov (United States)

    Fang, Jinbo; Luo, Ying; Li, Yanhua; Huang, Wenxia

    2016-11-01

    To describe social problem solving in Chinese baccalaureate nursing students. A descriptive cross-sectional study was conducted with a cluster sample of 681 Chinese baccalaureate nursing students. The Chinese version of the Social Problem-Solving scale was used. Descriptive analyses, independent t-test and one-way analysis of variance were applied to analyze the data. The final year nursing students presented the highest scores of positive social problem-solving skills. Students with experiences of self-directed and problem-based learning presented significantly higher scores in Positive Problem Orientation subscale. The group with Critical thinking training experience, however, displayed higher negative problem solving scores compared with nonexperience group. Social problem solving abilities varied based upon teaching-learning strategies. Self-directed and problem-based learning may be recommended as effective way to improve social problem-solving ability. © 2016 Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd.

  14. Using Analogy to Solve a Three-Step Physics Problem

    Science.gov (United States)

    Lin, Shih-Yin; Singh, Chandralekha

    2010-10-01

    In a companion paper, we discuss students' ability to take advantage of what they learn from a solved problem and transfer their learning to solve a quiz problem that has different surface features but the same underlying physics principles. Here, we discuss students' ability to perform analogical reasoning between another pair of problems. Both the problems can be solved using the same physics principles. However, the solved problem provided was a two-step problem (which can be solved by decomposing it into two sub-problems) while the quiz problem was a three-step problem. We find that it is challenging for students to extend what they learned from a two-step problem to solve a three-step problem.

  15. Affect and mathematical problem solving a new perspective

    CERN Document Server

    Adams, Verna

    1989-01-01

    Research on cognitive aspects of mathematical problem solving has made great progress in recent years, but the relationship of affective factors to problem-solving performance has been a neglected research area. The purpose of Affect and Mathematical Problem Solving: A New Perspective is to show how the theories and methods of cognitive science can be extended to include the role of affect in mathematical problem solving. The book presents Mandler's theory of emotion and explores its implications for the learning and teaching of mathematical problem solving. Also, leading researchers from mathematics, education, and psychology report how they have integrated affect into their own cognitive research. The studies focus on metacognitive processes, aesthetic influences on expert problem solvers, teacher decision-making, technology and teaching problem solving, and beliefs about mathematics. The results suggest how emotional factors like anxiety, frustration, joy, and satisfaction can help or hinder performance in...

  16. Self-affirmation improves problem-solving under stress.

    Science.gov (United States)

    Creswell, J David; Dutcher, Janine M; Klein, William M P; Harris, Peter R; Levine, John M

    2013-01-01

    High levels of acute and chronic stress are known to impair problem-solving and creativity on a broad range of tasks. Despite this evidence, we know little about protective factors for mitigating the deleterious effects of stress on problem-solving. Building on previous research showing that self-affirmation can buffer stress, we tested whether an experimental manipulation of self-affirmation improves problem-solving performance in chronically stressed participants. Eighty undergraduates indicated their perceived chronic stress over the previous month and were randomly assigned to either a self-affirmation or control condition. They then completed 30 difficult remote associate problem-solving items under time pressure in front of an evaluator. Results showed that self-affirmation improved problem-solving performance in underperforming chronically stressed individuals. This research suggests a novel means for boosting problem-solving under stress and may have important implications for understanding how self-affirmation boosts academic achievement in school settings.

  17. Improving mathematical problem solving ability through problem-based learning and authentic assessment for the students of Bali State Polytechnic

    Science.gov (United States)

    Darma, I. K.

    2018-01-01

    This research is aimed at determining: 1) the differences of mathematical problem solving ability between the students facilitated with problem-based learning model and conventional learning model, 2) the differences of mathematical problem solving ability between the students facilitated with authentic and conventional assessment model, and 3) interaction effect between learning and assessment model on mathematical problem solving. The research was conducted in Bali State Polytechnic, using the 2x2 experiment factorial design. The samples of this research were 110 students. The data were collected using a theoretically and empirically-validated test. Instruments were validated by using Aiken’s approach of technique content validity and item analysis, and then analyzed using anova stylistic. The result of the analysis shows that the students facilitated with problem-based learning and authentic assessment models get the highest score average compared to the other students, both in the concept understanding and mathematical problem solving. The result of hypothesis test shows that, significantly: 1) there is difference of mathematical problem solving ability between the students facilitated with problem-based learning model and conventional learning model, 2) there is difference of mathematical problem solving ability between the students facilitated with authentic assessment model and conventional assessment model, and 3) there is interaction effect between learning model and assessment model on mathematical problem solving. In order to improve the effectiveness of mathematics learning, collaboration between problem-based learning model and authentic assessment model can be considered as one of learning models in class.

  18. Diagnostic problem solving in male collegiate athletic trainers.

    Science.gov (United States)

    Gardin, Fredrick A; Mensch, James M

    2014-01-01

    Knowledge and experience may be important factors for understanding expertise based upon a clinician's ability to select and execute an appropriate response as a clinician during injury evaluation. To describe how collegiate male certified athletic trainers represent injury-evaluation domain knowledge during a situational interview using a think-aloud protocol. Qualitative. National Collegiate Athletic Association Division I and II colleges in National Athletic Trainers' Association District 3. A total of 20 male certified athletic trainers (n = 10 with less than 2 years of experience in the college setting and n = 10 with at least 10 years of experience in the college setting) participated in the study. We collected data using a situational interview and questionnaire. Data were transcribed, reduced to meaningful units, and analyzed using verbal analysis procedures. Member checks, triangulation of data, field journaling, and peer-debriefing techniques were used to ensure trustworthiness of the data. Knowledge concepts were enumerated to describe differences between experts and novices. Compared with novices, experts had more knowledge concepts of patient history and predictions and fewer concepts of situation appraisal. Expertise in athletic training shares traits with other areas in health care. Athletic training education and professional development may benefit from our understanding which cognitive processes differentiate expert practice. Future investigators should attempt to describe other settings and study diagnostic problem solving in a natural environment.

  19. Structuring students’ analogical reasoning in solving algebra problem

    Science.gov (United States)

    Lailiyah, S.; Nusantara, T.; Sa'dijah, C.; Irawan, E. B.; Kusaeri; Asyhar, A. H.

    2018-01-01

    The average achievement of Indonesian students’ mathematics skills according to Benchmark International Trends in Mathematics and Science Study (TIMSS) is ranked at the 38th out of 42 countries and according to the survey result in Program for International Student Assessment (PISA) is ranked at the 64th out of 65 countries. The low mathematics skill of Indonesian student has become an important reason to research more deeply about reasoning and algebra in mathematics. Analogical reasoning is a very important component in mathematics because it is the key to creativity and it can make the learning process in the classroom become effective. The major part of the analogical reasoning is about structuring including the processes of inferencing and decision-making happens. Those processes involve base domain and target domain. Methodologically, the subjects of this research were 42 students from class XII. The sources of data were derived from the results of thinks aloud, the transcribed interviews, and the videos taken while the subject working on the instruments and interviews. The collected data were analyzed using qualitative techniques. The result of this study described the structuring characteristics of students’ analogical reasoning in solving algebra problems from all the research subjects.

  20. Solving modified systems with multiple right-hand sides

    Energy Technology Data Exchange (ETDEWEB)

    Simoncini, V.; Gallopoulos, E. [Univ. of Patras (Greece)

    1996-12-31

    In this talk we discuss the iterative solution of large linear systems of the form (A + USV{sup H})X = B, where A is an n x n non-Hermitian matrix, USV{sup H} is a rank-r modification of A and B is of rank s with s, r {much_lt} n. We analyze several approaches that exploit the structure of the coefficient matrix so as to solve the systems more efficiently than if one were to apply a non-hermitian solver to the original systems. In the development of procedures, we take into account the presence of both the low-rank modification and the several right-hand sides. Interesting issues connected to this problem originate from the quest for techniques that accelerate the underlying iterative solvers: preconditioning (e.g. inner-outer iteration strategies), domain decomposition, and continuation methods. Experiments are provided to analyze the behavior of the methods depending on the structure of the rectangular matrices. Preconditioning strategies are explored for an efficient implementation on the transformed systems.

  1. Plausible inference: A multi-valued logic for problem solving

    Science.gov (United States)

    Friedman, L.

    1979-01-01

    A new logic is developed which permits continuously variable strength of belief in the truth of assertions. Four inference rules result, with formal logic as a limiting case. Quantification of belief is defined. Propagation of belief to linked assertions results from dependency-based techniques of truth maintenance so that local consistency is achieved or contradiction discovered in problem solving. Rules for combining, confirming, or disconfirming beliefs are given, and several heuristics are suggested that apply to revising already formed beliefs in the light of new evidence. The strength of belief that results in such revisions based on conflicting evidence are a highly subjective phenomenon. Certain quantification rules appear to reflect an orderliness in the subjectivity. Several examples of reasoning by plausible inference are given, including a legal example and one from robot learning. Propagation of belief takes place in directions forbidden in formal logic and this results in conclusions becoming possible for a given set of assertions that are not reachable by formal logic.

  2. An agent-oriented hierarchic strategy for solving inverse problems

    Directory of Open Access Journals (Sweden)

    Smołka Maciej

    2015-09-01

    Full Text Available The paper discusses the complex, agent-oriented hierarchic memetic strategy (HMS dedicated to solving inverse parametric problems. The strategy goes beyond the idea of two-phase global optimization algorithms. The global search performed by a tree of dependent demes is dynamically alternated with local, steepest descent searches. The strategy offers exceptionally low computational costs, mainly because the direct solver accuracy (performed by the hp-adaptive finite element method is dynamically adjusted for each inverse search step. The computational cost is further decreased by the strategy employed for solution inter-processing and fitness deterioration. The HMS efficiency is compared with the results of a standard evolutionary technique, as well as with the multi-start strategy on benchmarks that exhibit typical inverse problems’ difficulties. Finally, an HMS application to a real-life engineering problem leading to the identification of oil deposits by inverting magnetotelluric measurements is presented. The HMS applicability to the inversion of magnetotelluric data is also mathematically verified.

  3. Exploring students’ perceived and actual ability in solving statistical problems based on Rasch measurement tools

    Science.gov (United States)

    Azila Che Musa, Nor; Mahmud, Zamalia; Baharun, Norhayati

    2017-09-01

    One of the important skills that is required from any student who are learning statistics is knowing how to solve statistical problems correctly using appropriate statistical methods. This will enable them to arrive at a conclusion and make a significant contribution and decision for the society. In this study, a group of 22 students majoring in statistics at UiTM Shah Alam were given problems relating to topics on testing of hypothesis which require them to solve the problems using confidence interval, traditional and p-value approach. Hypothesis testing is one of the techniques used in solving real problems and it is listed as one of the difficult concepts for students to grasp. The objectives of this study is to explore students’ perceived and actual ability in solving statistical problems and to determine which item in statistical problem solving that students find difficult to grasp. Students’ perceived and actual ability were measured based on the instruments developed from the respective topics. Rasch measurement tools such as Wright map and item measures for fit statistics were used to accomplish the objectives. Data were collected and analysed using Winsteps 3.90 software which is developed based on the Rasch measurement model. The results showed that students’ perceived themselves as moderately competent in solving the statistical problems using confidence interval and p-value approach even though their actual performance showed otherwise. Item measures for fit statistics also showed that the maximum estimated measures were found on two problems. These measures indicate that none of the students have attempted these problems correctly due to reasons which include their lack of understanding in confidence interval and probability values.

  4. Matrix Methods for Solving Hartree-Fock Equations in Atomic Structure Calculations and Line Broadening

    Directory of Open Access Journals (Sweden)

    Thomas Gomez

    2018-04-01

    Full Text Available Atomic structure of N-electron atoms is often determined by solving the Hartree-Fock equations, which are a set of integro-differential equations. The integral part of the Hartree-Fock equations treats electron exchange, but the Hartree-Fock equations are not often treated as an integro-differential equation. The exchange term is often approximated as an inhomogeneous or an effective potential so that the Hartree-Fock equations become a set of ordinary differential equations (which can be solved using the usual shooting methods. Because the Hartree-Fock equations are an iterative-refinement method, the inhomogeneous term relies on the previous guess of the wavefunction. In addition, there are numerical complications associated with solving inhomogeneous differential equations. This work uses matrix methods to solve the Hartree-Fock equations as an integro-differential equation. It is well known that a derivative operator can be expressed as a matrix made of finite-difference coefficients; energy eigenvalues and eigenvectors can be obtained by using linear-algebra packages. The integral (exchange part of the Hartree-Fock equation can be approximated as a sum and written as a matrix. The Hartree-Fock equations can be solved as a matrix that is the sum of the differential and integral matrices. We compare calculations using this method against experiment and standard atomic structure calculations. This matrix method can also be used to solve for free-electron wavefunctions, thus improving how the atoms and free electrons interact. This technique is important for spectral line broadening in two ways: it improves the atomic structure calculations, and it improves the motion of the plasma electrons that collide with the atom.

  5. Removal of round off errors in the matrix exponential method for solving the heavy nuclide chain

    International Nuclear Information System (INIS)

    Lee, Hyun Chul; Noh, Jae Man; Joo, Hyung Kook

    2005-01-01

    Many nodal codes for core simulation adopt the micro-depletion procedure for the depletion analysis. Unlike the macro-depletion procedure, the microdepletion procedure uses micro-cross sections and number densities of important nuclides to generate the macro cross section of a spatial calculational node. Therefore, it needs to solve the chain equations of the nuclides of interest to obtain their number densities. There are several methods such as the matrix exponential method (MEM) and the chain linearization method (CLM) for solving the nuclide chain equations. The former solves chain equations exactly even when the cycles that come from the alpha decay exist in the chain while the latter solves the chain approximately when the cycles exist in the chain. The former has another advantage over the latter. Many nodal codes for depletion analysis, such as MASTER, solve only the hard coded nuclide chains with the CLM. Therefore, if we want to extend the chain by adding some more nuclides to the chain, we have to modify the source code. In contrast, we can extend the chain just by modifying the input in the MEM because it is easy to implement the MEM solver for solving an arbitrary nuclide chain. In spite of these advantages of the MEM, many nodal codes adopt the chain linearization because the former has a large round off error when the flux level is very high or short lived or strong absorber nuclides exist in the chain. In this paper, we propose a new technique to remove the round off errors in the MEM and we compared the performance of the two methods

  6. Solving optimisation problems in metal forming using Finite Element simulation and metamodelling techniques

    NARCIS (Netherlands)

    Bonte, M.H.A.; van den Boogaard, Antonius H.; Huetink, Han

    2005-01-01

    During the last decades, Finite Element (FEM) simulations of metal forming processes have become important tools for designing feasible production processes. In more recent years, several authors recognised the potential of coupling FEM simulations to mathematical optimisation algorithms to design

  7. A METHOD FOR SOLVING LINEAR PROGRAMMING PROBLEMS WITH FUZZY PARAMETERS BASED ON MULTIOBJECTIVE LINEAR PROGRAMMING TECHNIQUE

    OpenAIRE

    M. ZANGIABADI; H. R. MALEKI

    2007-01-01

    In the real-world optimization problems, coefficients of the objective function are not known precisely and can be interpreted as fuzzy numbers. In this paper we define the concepts of optimality for linear programming problems with fuzzy parameters based on those for multiobjective linear programming problems. Then by using the concept of comparison of fuzzy numbers, we transform a linear programming problem with fuzzy parameters to a multiobjective linear programming problem. To this end, w...

  8. SmArT solving : Tools and techniques for satisfiability solvers

    NARCIS (Netherlands)

    Heule, M.J.H.

    2008-01-01

    The satisfiability problem (Sat) lies at the core of the complexity theory. This is a decision problem: Not the solution itself, but whether or not a solution exists given a specified set of requirements is the central question. Over the years, the satisfiability problem has taken center stage as a

  9. Identifying Students for Intervention in Math Problem Solving: An Evaluation of Fluency-Based Word Problem Solving Measures

    OpenAIRE

    Sisco-Taylor, Dennis T.

    2014-01-01

    This study examined the extent to which initial performance, and growth on an experimental CBM word problem solving fluency measure (WPSF) were predictive of student performance on criterion measures of math problem solving. In addition, the extent to which WPSF could correctly classify students as a function of risk status was evaluated. Alternate forms of the WPSF measure were administered to 142 third grade students, along with multiple criterion measures of math problem solving. Results i...

  10. Combining Symbolic Representations for Solving Timed Games

    Science.gov (United States)

    Ehlers, Rüdiger; Mattmüller, Robert; Peter, Hans-Jörg

    We present a general approach to combine symbolic state space representations for the discrete and continuous parts in the synthesis of winning strategies for timed reachability games. The combination is based on abstraction refinement where discrete symbolic techniques are used to produce a sequence of abstract timed game automata. After each refinement step, the resulting abstraction is used for computing an under- and an over-approximation of the timed winning states. The key idea is to identify large relevant and irrelevant parts of the precise weakest winning strategy already on coarse, and therefore simple, abstractions. If neither the existence nor nonexistence of a winning strategy can be established in the approximations, we use them to guide the refinement process. Based on a prototype that combines binary decision diagrams[7,9] and difference bound matrices[5], we experimentally evaluate the technique on standard benchmarks from timed controller synthesis. The results clearly demonstrate the potential of the new approach concerning running time and memory consumption compared to the classical on-the-fly algorithm implemented in Uppaal-Tiga [10,4].

  11. How do they solve it? An insight into the learner’s approach to the mechanism of physics problem solving

    Directory of Open Access Journals (Sweden)

    Balasubrahmanya Hegde

    2012-03-01

    Full Text Available A perceived difficulty is associated with physics problem solving from a learner’s viewpoint, arising out of a multitude of reasons. In this paper, we have examined the microstructure of students’ thought processes during physics problem solving by combining the analysis of responses to multiple-choice questions and semistructured student interviews. Design of appropriate scaffoldings serves as pointers to the identification of student problem solving difficulties. An analysis of the results suggests the necessity of identification of the skill sets required for developing better problem solving abilities.

  12. Solving the minimum flow problem with interval bounds and flows

    Indian Academy of Sciences (India)

    ... with crisp data. In this paper, the idea of Ghiyasvand was extended for solving the minimum flow problem with interval-valued lower, upper bounds and flows. This problem can be solved using two minimum flow problems with crisp data. Then, this result is extended to networks with fuzzy lower, upper bounds and flows.

  13. George Pólya & Problem Solving ... An Appreciation

    Indian Academy of Sciences (India)

    IAS Admin

    Studying the methods of solving problems, we perceive another face of ... [For] example, group theory has concentrated ideas which formerly were found ... great contributions was in bringing energy and attention to bear on the field of pedagogy. Agreatdiscovery solves a great problem but there is a grain of discovery in the.

  14. The Effects of Iliad on Medical Student Problem Solving

    OpenAIRE

    Turner, Charles W.; Williamson, John; Lincoln, Michael J.; Haug, Peter J.; Buchanan, James; Anderson, Curtis; Grant, Morgan; Cundick, Robert; Warner, Homer R.

    1990-01-01

    The present study examined the effects of the Iliad expert system on diagnostic problem solving of third-year (n = 97) medical students. Students used Iliad to work-up simulated cases to supplement the education they received in their medicine clerkship. The results of the research provided evidence that the Iliad expert system did improve student diagnostic problem solving and decision making.

  15. The Effect of Strategy on Problem Solving: An FMRI Study

    Science.gov (United States)

    Newman, Sharlene D.; Pruce, Benjamin; Rusia, Akash; Burns, Thomas, Jr.

    2010-01-01

    fMRI was used to examine the differential effect of two problem-solving strategies. Participants were trained to use both a pictorial/spatial and a symbolic/algebraic strategy to solve word problems. While these two strategies activated similar cortical regions, a number of differences were noted in the level of activation. These differences…

  16. Problem Solving Frameworks for Mathematics and Software Development

    Science.gov (United States)

    McMaster, Kirby; Sambasivam, Samuel; Blake, Ashley

    2012-01-01

    In this research, we examine how problem solving frameworks differ between Mathematics and Software Development. Our methodology is based on the assumption that the words used frequently in a book indicate the mental framework of the author. We compared word frequencies in a sample of 139 books that discuss problem solving. The books were grouped…

  17. Relationship between Problem-Solving Ability and Career Maturity ...

    African Journals Online (AJOL)

    This study investigated the relationship between problem-solving ability and career maturity of secondary school students in Ibadan, Oyo State, Nigeria. 230 final year secondary school students completed self-report measures of problem solving and career maturity. Multiple regression analysis was used to analyse the data ...

  18. Solving the uncalibrated photometric stereo problem using total variation

    DEFF Research Database (Denmark)

    Quéau, Yvain; Lauze, Francois Bernard; Durou, Jean-Denis

    2013-01-01

    In this paper we propose a new method to solve the problem of uncalibrated photometric stereo, making very weak assumptions on the properties of the scene to be reconstructed. Our goal is to solve the generalized bas-relief ambiguity (GBR) by performing a total variation regularization of both...

  19. Basic school pupils' strategies in solving subtraction problems ...

    African Journals Online (AJOL)

    This article reports some of the strategies basic schools children apply in solving subtraction problems. The purpose of the study was to see whether the semantic structure of mathematical problems influences children's choice of strategy in solving a subtraction problem. Mathematics Connection Vol. 4 2004: 31-37 ...

  20. Using problem-solving instruction to overcome high school ...

    African Journals Online (AJOL)

    Using problem-solving instruction to overcome high school chemistry students' difficulties with stoichiometric problems. ... African Journal of Educational Studies in Mathematics and Sciences ... The study sought to find out the difficulties encountered by high school chemistry students when solving stoichiometric problems.

  1. Assessment for Intervention: A Problem Solving Approach. Second Edition

    Science.gov (United States)

    Brown­ Chidsey, Rachel, Ed.; Andren, Kristina J., Ed.

    2015-01-01

    Problem-­solving assessment is an essential component of multi-­tiered systems of support such as response to intervention (RTI) and positive behavioral interventions and supports (PBIS). This authoritative work provides a complete guide to implementing a wide range of problem­-solving assessment methods, including: (1) functional behavioral…

  2. Instructional Design-Based Research on Problem Solving Strategies

    Science.gov (United States)

    Emre-Akdogan, Elçin; Argün, Ziya

    2016-01-01

    The main goal of this study is to find out the effect of the instructional design method on the enhancement of problem solving abilities of students. Teaching sessions were applied to ten students who are in 11th grade, to teach them problem solving strategies which are working backwards, finding pattern, adopting a different point of view,…

  3. Teaching Problem-Solving Skills to Nuclear Engineering Students

    Science.gov (United States)

    Waller, E.; Kaye, M. H.

    2012-01-01

    Problem solving is an essential skill for nuclear engineering graduates entering the workforce. Training in qualitative and quantitative aspects of problem solving allows students to conceptualise and execute solutions to complex problems. Solutions to problems in high consequence fields of study such as nuclear engineering require rapid and…

  4. Using Everyday Materials To Promote Problem Solving in Toddlers.

    Science.gov (United States)

    Segatti, Laura; Brown-DuPaul, Judy; Keyes, Tracy L.

    2003-01-01

    Outlines benefits of and skills involved in problem solving. Details how an environment rich in materials that foster cause-and-effect or trial-and-error explorations promote cognitive development among toddlers. Offers examples of problem-solving experiences and lists materials for use in curriculum planning. Describes the teacher' role as one of…

  5. Strategies, Not Solutions: Involving Students in Problem Solving.

    Science.gov (United States)

    Von Kuster, Lee N.

    1984-01-01

    Defines problem solving, discusses the use of problems developed by students that are relevant to their own lives, presents examples of practical mathematics problems that deal with local situations, discusses fringe benefits of this type of problem solving, and addresses teachers' concern that this method consumes too much time. (MBR)

  6. Explanation and the Theory of Expert Problem Solving

    Science.gov (United States)

    1990-02-01

    clasification strategy for diagrsls. Bennett [21 presents COAST, a shell for the design of configuration problem solving systems. All these approaches share the...category may exist in more than one 1) Not all classification problems are nece ssaiily solved classification hierarchy, e.g.. viral hepatitis is a con- as

  7. students' preference of method of solving simultaneous equations

    African Journals Online (AJOL)

    Ugboduma,Samuel.O.

    More so, they will be reposition in order to solve other mathematical problems involving applications of simultaneous equations methods of solutions. Research questions. The following research questions were asked: i what proportion of SSS2 students showed preference for one type of method of solving simultaneous.

  8. An approach for solving linear fractional programming problems ...

    African Journals Online (AJOL)

    An approach for solving linear fractional programming problems. ... Journal of the Nigerian Association of Mathematical Physics ... The paper presents a new approach for solving a fractional linear programming problem in which the objective function is a linear fractional function, while the constraint functions are in the form ...

  9. Social Problem Solving and Aggression: The Role of Depression

    Science.gov (United States)

    Ozdemir, Yalcin; Kuzucu, Yasar; Koruklu, Nermin

    2013-01-01

    The purpose of the present study was to examine direct and indirect relations among social problem-solving, depression, and aggression, as well as the mediating role of depression in the link between social problem-solving and aggression among Turkish youth. Data for the present study were collected from 413 adolescents. The participants' age…

  10. Problem solving and problem strategies in the teaching and learning ...

    African Journals Online (AJOL)

    Perennial poor performance recorded annually in both internal and external examinations in Mathematics has been a great concern for the Mathematics Educators in Nigeria. This paper discusses problem-solving and influence of problem-solving strategies on students' performance in mathematics. The concept of ...

  11. The Effects of Service Learning on Student Problem Solving

    Science.gov (United States)

    Guo, Fangfang; Yao, Meilin; Wang, Cong; Yan, Wenfan; Zong, Xiaoli

    2016-01-01

    Previous research indicated that service learning (SL) is an effective pedagogy to improve students' problem-solving ability and increase their classroom engagement. However, studies on SL are rare in China. This study examined the effects of SL on the problem solving of Chinese undergraduate students as well as the mechanism through which it…

  12. Cognitive Load in Algebra: Element Interactivity in Solving Equations

    Science.gov (United States)

    Ngu, Bing Hiong; Chung, Siu Fung; Yeung, Alexander Seeshing

    2015-01-01

    Central to equation solving is the maintenance of equivalence on both sides of the equation. However, when the process involves an interaction of multiple elements, solving an equation can impose a high cognitive load. The balance method requires operations on both sides of the equation, whereas the inverse method involves operations on one side…

  13. Fourth order compact finite difference method for solving singularly ...

    African Journals Online (AJOL)

    A numerical method based on finite difference scheme with uniform mesh is presented for solving singularly perturbed two-point boundary value problems of 1D reaction-diffusion equations. First, the derivatives of the given differential equation is replaced by the finite difference approximations and then, solved by using ...

  14. A Markov Model Analysis of Problem-Solving Progress.

    Science.gov (United States)

    Vendlinski, Terry

    This study used a computerized simulation and problem-solving tool along with artificial neural networks (ANN) as pattern recognizers to identify the common types of strategies high school and college undergraduate chemistry students would use to solve qualitative chemistry problems. Participants were 134 high school chemistry students who used…

  15. Identification of Strategies Used in Solving Transformational Geometry Problems.

    Science.gov (United States)

    Boulter, Douglas R.; Kirby, John R.

    1994-01-01

    Study investigated how to characterize students' transformational geometry problem-solving strategies, how strategies characterized particular subjects, and how strategy usage related to performance. Videotapes indicated problem-solving responses could be classified consistently, some students preferred holistic processing, some items readily…

  16. Problem Solving through an Optimization Problem in Geometry

    Science.gov (United States)

    Poon, Kin Keung; Wong, Hang-Chi

    2011-01-01

    This article adapts the problem-solving model developed by Polya to investigate and give an innovative approach to discuss and solve an optimization problem in geometry: the Regiomontanus Problem and its application to football. Various mathematical tools, such as calculus, inequality and the properties of circles, are used to explore and reflect…

  17. The Stages of Student Mathematical Imagination in Solving Mathematical Problems

    Science.gov (United States)

    Wibowo, Teguh; Sutawidjaja, Akbar; As'ari, Abdur Rahman; Sulandra, I. Made

    2017-01-01

    This research is a qualitative study that aimed to describe the stages of students mathematical imagination in solving mathematical problems. There are three kinds of mathematical imagination in solving mathematical problems, namely sensory mathematical imagination, creative mathematical imagination and recreative mathematical imagination.…

  18. Solving L-L Extraction Problems with Excel Spreadsheet

    Science.gov (United States)

    Teppaitoon, Wittaya

    2016-01-01

    This work aims to demonstrate the use of Excel spreadsheets for solving L-L extraction problems. The key to solving the problems successfully is to be able to determine a tie line on the ternary diagram where the calculation must be carried out. This enables the reader to analyze the extraction process starting with a simple operation, the…

  19. Facilitating Flexible Problem Solving: A Cognitive Load Perspective

    Science.gov (United States)

    Kalyuga, Slava; Renkl, Alexander; Paas, Fred

    2010-01-01

    The development of flexible, transferable problem-solving skills is an important aim of contemporary educational systems. Since processing limitations of our mind represent a major factor influencing any meaningful learning, the acquisition of flexible problem-solving skills needs to be based on known characteristics of our cognitive architecture…

  20. Adams Predictor-Corrector Systems for Solving Fuzzy Differential Equations

    Directory of Open Access Journals (Sweden)

    Dequan Shang

    2013-01-01

    Full Text Available A predictor-corrector algorithm and an improved predictor-corrector (IPC algorithm based on Adams method are proposed to solve first-order differential equations with fuzzy initial condition. These algorithms are generated by updating the Adams predictor-corrector method and their convergence is also analyzed. Finally, the proposed methods are illustrated by solving an example.

  1. A problem solving model for regulatory policy making

    NARCIS (Netherlands)

    Boer, A.; van Engers, T.; Sileno, G.; Wyner, A.; Benn, N.

    2011-01-01

    In this paper we discuss how the interests and field theory promoted by public administration as a stakeholder in policy argumentation, directly arise from its problem solving activities, using the framework for public administration problem solving we proposed in [1,2]. We propose that calls for

  2. Problem Solving and Collaboration Using Mobile Serious Games

    Science.gov (United States)

    Sanchez, Jaime; Olivares, Ruby

    2011-01-01

    This paper presents the results obtained with the implementation of a series of learning activities based on Mobile Serious Games (MSGs) for the development of problem solving and collaborative skills in Chilean 8th grade students. Three MSGs were developed and played by teams of four students in order to solve problems collaboratively. A…

  3. Using Systemic Problem Solving (SPS) to Assess Student ...

    African Journals Online (AJOL)

    However, systemic problem solving (SPS) can challenge students and probe higher cognitive skills like analysis, synthesis, and evaluation. Also, systemic problem solving (SPS) helps students to connect chemistry concepts, and facts and covers a wide range of intended learning outcomes (ILO,s). As an example, the type ...

  4. Problem Solving Treatment for Intellectually Disabled Sex Offenders

    Science.gov (United States)

    Nezu, Christine Maguth; Fiore, Alicia A.; Nezu, Arthur M.

    2006-01-01

    Over the past thirty years, Problem Solving Therapy (PST) has been shown to be an effective treatment for many different problems and patient populations (Nezu, 2004). Among its many clinical applications, PST interventions were developed for persons with intellectually disabilities (ID), where improving problem-solving skills led to adaptive…

  5. Working memory dysfunctions predict social problem solving skills in schizophrenia.

    Science.gov (United States)

    Huang, Jia; Tan, Shu-ping; Walsh, Sarah C; Spriggens, Lauren K; Neumann, David L; Shum, David H K; Chan, Raymond C K

    2014-12-15

    The current study aimed to examine the contribution of neurocognition and social cognition to components of social problem solving. Sixty-seven inpatients with schizophrenia and 31 healthy controls were administrated batteries of neurocognitive tests, emotion perception tests, and the Chinese Assessment of Interpersonal Problem Solving Skills (CAIPSS). MANOVAs were conducted to investigate the domains in which patients with schizophrenia showed impairments. Correlations were used to determine which impaired domains were associated with social problem solving, and multiple regression analyses were conducted to compare the relative contribution of neurocognitive and social cognitive functioning to components of social problem solving. Compared with healthy controls, patients with schizophrenia performed significantly worse in sustained attention, working memory, negative emotion, intention identification and all components of the CAIPSS. Specifically, sustained attention, working memory and negative emotion identification were found to correlate with social problem solving and 1-back accuracy significantly predicted the poor performance in social problem solving. Among the dysfunctions in schizophrenia, working memory contributed most to deficits in social problem solving in patients with schizophrenia. This finding provides support for targeting working memory in the development of future social problem solving rehabilitation interventions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. expansion method for solving nonlinear space–time fractional ...

    Indian Academy of Sciences (India)

    2016-07-06

    Jul 6, 2016 ... -expansion method for solving fractional differential equations based on a fractional complex transform. We apply this method for solving space–time fractional Cahn–Allen equation and space–time fractional Klein–Gordon equation. The fractional derivatives are described in the sense of modified ...

  7. DEVELOPMENT OF TEACHING MATERIALS ALGEBRAIC EQUATION TO IMPROVE PROBLEM SOLVING

    Directory of Open Access Journals (Sweden)

    sri adi widodo

    2017-01-01

    Full Text Available Problem-solving skills are the basic capabilities of a person in solving a problem and that involve critical thinking, logical, and systematic. To solve a problem one-way necessary measures to solve the problem. Polya is one way to solve a mathematical problem. by developing teaching materials designed using the steps in solving problems Polya expected students could improve its ability to solve problems. In this first year, the goal of this study is to investigate the process of learning the hypothetical development of teaching materials. This study is a research & development. Procedure development research refers to research the development of Thiagarajan, Semmel & Semmel ie 4-D. Model development in the first year is define, design, and development. The collection of data for the assessment of teaching materials algebra equations conducted by the expert by filling the validation sheet. Having examined the materials of algebraic equations in the subject of numerical methods, reviewing the curriculum that is aligned with KKNI, and formulates learning outcomes that formed the conceptual teaching material on the material algebraic equations. From the results of expert assessment team found that the average ratings of teaching materials in general algebraic equation of 4.38 with a very good category. The limited test needs to be done to see effectiveness teaching materials on problem-solving skills in students who are taking courses numerical methods

  8. Students' Epistemological Framing in Quantum Mechanics Problem Solving

    Science.gov (United States)

    Modir, Bahar; Thompson, John D.; Sayre, Eleanor C.

    2017-01-01

    Students' difficulties in quantum mechanics may be the result of unproductive framing and not a fundamental inability to solve the problems or misconceptions about physics content. We observed groups of students solving quantum mechanics problems in an upper-division physics course. Using the lens of epistemological framing, we investigated four…

  9. Dimensional Analysis and Qualitative Methods in Problem Solving

    Science.gov (United States)

    Pescetti, D.

    2008-01-01

    The primary application of dimensional analysis (DA) is in problem solving. Typically, the problem description indicates that a physical quantity Y(the unknown) is a function f of other physical quantities A[subscript 1], ..., A[subscript n] (the data). We propose a qualitative problem-solving procedure which consists of a parallel decomposition…

  10. Measuring Problem Solving Skills in Plants vs. Zombies 2

    Science.gov (United States)

    Shute, Valerie J.; Moore, Gregory R.; Wang, Lubin

    2015-01-01

    We are using stealth assessment, embedded in "Plants vs. Zombies 2," to measure middle-school students' problem solving skills. This project started by developing a problem solving competency model based on a thorough review of the literature. Next, we identified relevant in-game indicators that would provide evidence about students'…

  11. Structured collaboration versus individual learning in solving physics problems

    NARCIS (Netherlands)

    Harskamp, Egbert; Ding, Ning

    2006-01-01

    The research issue in this study is how to structure collaborative learning so that it improves solving physics problems more than individual learning. Structured collaborative learning has been compared with individual learning environments with Schoenfeld's problem-solving episodes. Students took

  12. Teaching problem-solving competency in Business Studies at ...

    African Journals Online (AJOL)

    10218122

    solving can broadly be conceptualised as a process that includes five steps. During the teaching of problem-solving, the teacher should focus on the following steps that have to be executed by the learners (Crebert et al., 2011:10-. 11; Tull, 2012:1-2), ...

  13. Extricating Justification Scheme Theory in Middle School Mathematical Problem Solving

    Science.gov (United States)

    Matteson, Shirley; Capraro, Mary Margaret; Capraro, Robert M.; Lincoln, Yvonna S.

    2012-01-01

    Twenty middle grades students were interviewed to gain insights into their reasoning about problem-solving strategies using a Problem Solving Justification Scheme as our theoretical lens and the basis for our analysis. The scheme was modified from the work of Harel and Sowder (1998) making it more broadly applicable and accounting for research…

  14. Solving Microbial Spoilage Problems in Processed Foods

    Science.gov (United States)

    Clavero, Rocelle

    This chapter surveys common microbial food spoilage processes. The chapter is organized by food products and includes sections addressing spoilage in meat, poultry, fish; dairy products (milk, butter, cheese); beverage products; bakery products; canned foods; fruit and confectionery products; and emulsions. It addresses the isolation and identification of spoilage organisms and provides several case studies as examples. It introduces various organisms responsible for spoilage including Gram-positive lactic acid bacteria, Gram-negative aerobic bacteria, yeasts, molds, and fungal contaminants. Throughout the chapter, attention is given to when, where, and how spoilage organisms enter the food processing chain. Troubleshooting techniques are suggested. The effect (or lack of effect) of heating, dehydration, pH change, cooling, and sealing on various organisms is explained throughout. The chapter contains four tables that connect specific organisms to various spoilage manifestations in a variety of food products.

  15. Solving inverse problems of optical microlithography

    Science.gov (United States)

    Granik, Yuri

    2005-05-01

    The direct problem of microlithography is to simulate printing features on the wafer under given mask, imaging system, and process characteristics. The goal of inverse problems is to find the best mask and/or imaging system and/or process to print the given wafer features. In this study we will describe and compare solutions of inverse mask problems. Pixel-based inverse problem of mask optimization (or "layout inversion") is harder than inverse source problem, especially for partially-coherent systems. It can be stated as a non-linear constrained minimization problem over complex domain, with large number of variables. We compare method of Nashold projections, variations of Fienap phase-retrieval algorithms, coherent approximation with deconvolution, local variations, and descent searches. We propose electrical field caching technique to substantially speedup the searching algorithms. We demonstrate applications of phase-shifted masks, assist features, and maskless printing.

  16. A universal concept based on cellular neural networks for ultrafast and flexible solving of differential equations.

    Science.gov (United States)

    Chedjou, Jean Chamberlain; Kyamakya, Kyandoghere

    2015-04-01

    This paper develops and validates a comprehensive and universally applicable computational concept for solving nonlinear differential equations (NDEs) through a neurocomputing concept based on cellular neural networks (CNNs). High-precision, stability, convergence, and lowest-possible memory requirements are ensured by the CNN processor architecture. A significant challenge solved in this paper is that all these cited computing features are ensured in all system-states (regular or chaotic ones) and in all bifurcation conditions that may be experienced by NDEs.One particular quintessence of this paper is to develop and demonstrate a solver concept that shows and ensures that CNN processors (realized either in hardware or in software) are universal solvers of NDE models. The solving logic or algorithm of given NDEs (possible examples are: Duffing, Mathieu, Van der Pol, Jerk, Chua, Rössler, Lorenz, Burgers, and the transport equations) through a CNN processor system is provided by a set of templates that are computed by our comprehensive templates calculation technique that we call nonlinear adaptive optimization. This paper is therefore a significant contribution and represents a cutting-edge real-time computational engineering approach, especially while considering the various scientific and engineering applications of this ultrafast, energy-and-memory-efficient, and high-precise NDE solver concept. For illustration purposes, three NDE models are demonstratively solved, and related CNN templates are derived and used: the periodically excited Duffing equation, the Mathieu equation, and the transport equation.

  17. A Systematic Approach for Solving the Great Circle Track Problems based on Vector Algebra

    Directory of Open Access Journals (Sweden)

    Chen Chih-Li

    2016-04-01

    Full Text Available A systematic approach, based on multiple products of the vector algebra (S-VA, is proposed to derive the spherical triangle formulae for solving the great circle track (GCT problems. Because the mathematical properties of the geometry and algebra are both embedded in the S-VA approach, derivations of the spherical triangle formulae become more understandable and more straightforward as compared with those approaches which use the complex linear combination of a vector basis. In addition, the S-VA approach can handle all given initial conditions for solving the GCT problems simpler, clearer and avoid redundant formulae existing in the conventional approaches. With the technique of transforming the Earth coordinates system of latitudes and longitudes into the Cartesian one and adopting the relative longitude concept, the concise governing equations of the S-VA approach can be easily and directly derived. Owing to the advantage of the S-VA approach, it makes the practical navigator quickly adjust to solve the GCT problems. Based on the S-VA approach, a program namely GCTPro_VA is developed for friendly use of the navigator. Several validation examples are provided to show the S-VA approach is simple and versatile to solve the GCT problems.

  18. Limitations in direct and indirect methods for solving optimal control problems in growth theory

    Directory of Open Access Journals (Sweden)

    Ratković Kruna

    2016-01-01

    Full Text Available The focus of this paper is on a comprehensive analysis of different methods and mathematical techniques used for solving optimal control problems (OCP in growth theory. Most important methods for solving dynamic non-linear infinite-horizon growth models using optimal control theory are presented and a critical view of the limitations of different methods is given. The main problem is to determine the optimal rate of growth over time in a way that maximizes the welfare function over an infinite horizon. The welfare function depends on capital-labor ratio, the state variable, and the per-capita consumption, the control variable. Numerical methods for solving OCP are divided into two classes: direct and indirect approach. How the indirect approach can be used is given in the example of the neo-classical growth model. In order to present the indirect and the direct approach simultaneously, two endogenous growth models, one written by Romer and another by Lucas and Uzawa, are studied. Advantages and efficiency of these different approaches will be discussed. Although the indirect methods for solving OCP are still the most expanded in growth theory, it will be seen that using direct methods can also be very efficient and help to overcome problems that can occur by using the indirect approach.

  19. Upper bound of errors in solving the inverse problem of identifying a voice source

    Science.gov (United States)

    Leonov, A. S.; Sorokin, V. N.

    2017-09-01

    The paper considers the inverse problem of finding the shape of a voice-source pulse from a specified segment of a speech signal using a special mathematical model that relates these quantities. A variational method for solving the formulated inverse problem for two new parametric classes of sources is proposed: a piecewise-linear source and an A-source. The error in the obtained approximate solutions of the inverse problem is considered, and a technique to numerically estimate this error is proposed, which is based on the theory of a posteriori estimates of the accuracy in solving ill-posed problems. A computer study of the adequacy of the proposed models of sources, and a study of the a posteriori estimates of the accuracy in solving inverse problems for such sources were performed using various types of voice signals. Numerical experiments for speech signals showed satisfactory properties of such a posteriori estimates, which represent the upper bounds of possible errors in solving the inverse problem. The estimate of the most probable error in determining the source-pulse shapes for the investigated speech material is on average 7%. It is noted that the a posteriori accuracy estimates can be used as a criterion for the quality of determining the voice-source pulse shape in the speaker-identification problem.

  20. Analyzing problem solving using math in physics: Epistemological framing via warrants

    Directory of Open Access Journals (Sweden)

    Thomas J. Bing

    2009-12-01

    Full Text Available Developing expertise in physics entails learning to use mathematics effectively and efficiently as applied to the context of physical situations. Doing so involves coordinating a variety of concepts and skills including mathematical processing, computation, blending ancillary information with the math, and reading out physical implications from the math and vice versa. From videotaped observations of intermediate level students solving problems in groups, we note that students often “get stuck” using a limited group of skills or reasoning and fail to notice that a different set of tools (which they possess and know how to use effectively could quickly and easily solve their problem. We refer to a student’s perception or judgment of the kind of knowledge that is appropriate to bring to bear in a particular situation as epistemological framing. Although epistemological framing is often unstated (and even unconscious, in group problem-solving situations students sometimes get into disagreements about how to progress. During these disagreements, they bring forth reasons or warrants in support of their point of view. For the context of mathematics use in physics problem solving, we present a system for classifying physics students’ warrants and analyze a case study. This warrant analysis provides a general widely applicable technique for identifying students’ epistemological framings.