39 research outputs found

    Strict Solution Method for Linear Programming Problem with Ellipsoidal Distributions under Fuzziness

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    This paper considers a linear programming problem with ellipsoidal distributions including fuzziness. Since this problem is not well-defined due to randomness and fuzziness, it is hard to solve it directly. Therefore, introducing chance constraints, fuzzy goals and possibility measures, the proposed model is transformed into the deterministic equivalent problems. Furthermore, since it is difficult to solve the main problem analytically and efficiently due to nonlinear programming, the solution method is constructed introducing an appropriate parameter and performing the equivalent transformations

    Portfolio Selection Problems with Normal Mixture Distributions Including Fuzziness

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    In this paper, several portfolio selection problems with normal mixture distributions including fuzziness are proposed. Until now, many researchers have proposed portfolio models based on the stochastic approach, and there are some models considering both random and ambiguous conditions, particularly using fuzzy random or random fuzzy variables. However, the model including normal mixture distributions with fuzzy numbers has not been proposed yet. Our proposed problems are not well-defined problems due to randomness and fuzziness. Therefore, setting some criterions and introducing chance constrains, main problems are transformed into deterministic programming problems. Finally, we construct a solution method to obtain a global optimal solution of the problem

    Ispitivanje demonstracijskog postrojenja plinske turbine zatvorenog ciklusa s nadkritičnim CO2 kao radnim medijem

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    The development of a closed cycle gas turbine with super-critical carbon dioxide as a working fluid is under way in order to generate power from waste heat source of a low or intermediate temperature range from industry. Its demonstration test plan using a reduced scale turbomachine is described. Principal specifications follow; net power output of around 10 kWe and recirculation CO2 flow rate of 1.2 kg/s. Optimized range of compressor inlet temperatures as well as pressure is investigated under the given turbine inlet conditions of 550 K and 12 MPa respectively. Given these inlet conditions, a suitable type of turbomachine is selected to be radial. Based on the conventional design method assuming ideal gas an optimal dimension of the outer wheel diameter is predicted to be 20mm for compressor and 30mm for turbine under an optimal rotational speed of 100,000 min-1.U tijeku je razvoj plinske turbine zatvorenog ciklusa s nadkritičnim ugljikovim dioksidom kao radnim medijem za proizvodnju električne energije iz nisko ili srednje temperaturne otpadne topline iz industrije. Opisano je ispitivanje demonstracijskog postrojenja s turbinom u umanjenom mjerilu. Glavne karakteristike su: neto izlazna snaga od približno 10 kWe i protokom CO2 od 1.2 kg/s. Istraživano je optimalno područje ulaznih temperatura i tlakova kompresora za zadane ulazne parametre turbine od 550 K i 12 MPa. Za zadane ulazne uvjete, odabran je kao odgovarajući radijalni tip turbostroja. Na temelju uobičajenih metoda konstruiranja i pretpostavljajući idealni plin određene su optimalne vrijednosti vanjskih promjera rotora kompresora 20 mm i rotora turbine 30 mm uz optimalnu brzinu vrtnje od 100.000 min-1

    Risk-Controlled Multiobjective Portfolio Selection Problem Using a Principle of Compromise

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    This paper proposes a multiobjective portfolio selection problem with most probable random distribution derived from current market data and other random distributions of boom and recession under the risk-controlled parameters determined by an investor. The current market data and information include not only historical data but also interpretations of economists’ oral and linguistic information, and hence, the boom and recession are often caused by these nonnumeric data. Therefore, investors need to consider several situations from most probable condition to boom and recession and to avoid the risk less than the target return in each situation. Furthermore, it is generally difficult to set random distributions of these cases exactly. Therefore, a robust-based approach for portfolio selection problems using the only mean values and variances of securities is proposed as a multiobjective programming problem. In addition, an exact algorithm is developed to obtain an explicit optimal portfolio using a principle of compromise

    Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

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    OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

    Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

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    The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension
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