Gazdasági döntések modellezése = Economic Decision Models

A kutatás legfontosabb eredményei a többségében angol nyelvű referált folyóiratcikket tartalmazó közleményjegyzék 54 tételében jelennek meg, itt néhány témát emelünk ki. A többszempontú döntési problémák megoldásánál az AHP módszertannál felmerülő becslési és inkonzisztencia problémákra adtunk új megoldásokat. A döntéstámogatási alkalmazások során az ökológiai, környezeti és humán információk integrálására adtunk modell-javaslatot. Elemeztük a levegőszennyezés modellezését és játékelméleti modelleket alkalmaztunk klímaváltozási tárgyalásokkal kapcsolatosan. A nemlineáris programozással foglalkozó kutatások során új, hatékony módszereket vezettünk be a feladatok struktúráinak felismerésére és a redundancia kiszűrésére. Valószínűséggel korlátozott lineáris programozási feladatot oldottunk meg és vizsgáltuk a módszer konvergenciáját különböző eltérésfüggvények esetében. A globális optimalizálás témakörében például Stiefel sokaságon történő optimalizálásra adtunk új eredményeket. A statisztikai elméleti munkák és alkalmazások során elemeztük a biztosítási üzletág fejlődési tendenciáját egyes európai országokban. Egy másik kutatás az 1990-es évek nyugdíjreformja és a hosszabbodó várható élettartam miatt bekövetkező csökkenő halálozás hatását vizsgálja a három pilléressé alakított nyugdíjrendszer stabilitására. Ebbe a sorba tartoznak azok a legújabb cikkek, amelyek a magánnyugdíjak közötti választásról, illetve a magyar öngondoskodás sajátosságairól szólnak. | The most important results of our research can be found in the 54 items of the publication list. We can mention only a few of them here. In the area of multiattribute decision making we applied new approaches to solve estimation and inconsistency problems in AHP. A new model was proposed to integrate ecological, environmental and human information in decision support systems. Other applications have been introduced using air-pollution modeling. Climate change negotiations were analyzed with the help of game-theoretic models. In the field of nonlinear programming new, efficient methods have been introduced to recognize the structure of a given problem, and to eliminate redundancy. A probability constrained linear programming model was solved, and we analyzed the convergence of the method with different distance functions. Global optimization problems on Stiefel manifolds have also been investigated. One of the results in our theoretical and empirical statistical work was the analysis of the development trends in the insurance industry in Europe. An other research was focusing on the impact of the pension reform of the 1990?s and the declining mortality rate (due to the longer expected lifetime) to the new three-pillar pension system. Our latest publications deal with the choice among private pension funds, and with the specifics of the Hungarian self-insurance

Pareto improvement and joint cash management optimisation for banks and cash-in-transit firms

Improving the ATM cash management techniques of banks has already received significant attention in the literature as a separate optimisation problem for banks and the independent firms that supply cash to automated teller machines. This article concentrates instead on a further possibility of cost reduction: optimising the cash management problem as one single problem. Doing so, contractual prices between banks and the cash in transit firms can be in general modified allowing for further cost reduction rela- tive to individual optimisations. In order to show the pertinence of this procedure, we have determined possible Pareto-improvement re-contracting schemes based on a Baumol-type cash demand forecast for a Hungarian commercial bank resulting in substantial cost reduction

Pontszerű szennyező források tájra gyakorolt hatásának vizsgálata = Examinations on the effects on landscapes of point-sources of pollution

A talajszennyező forrásokat Mikepércs és Újszentmargita települési folyékonyhulladék-leürítője esetében vizsgáltuk. E szennyező források körül béléscsövezett furatokat létesítettünk. A talaj- és vízminták alapján megállapítottuk, hogy bár vannak eltérések, általában hasonló szennyezési tendenciák tapasztalhatók. Mindkét helyszínen jelentős ammónium- és nitrát-szennyezést mutattunk ki, a legjobb szennyezés-terjedési indikátornak pedig, a Na+ bizonyult. A szennyezés néhány száz méteres távolságig volt kimutatható. A pontszerű légszennyező források közül a pálházai perlitbánya szennyező hatását vizsgáltuk. Megállapítottuk, hogy csak a bánya néhány száz méteres körzetén belül kell jelentősebb porterheléssel számolnunk. Ebben a zónában előfordultak az egészségügyi határértéket meghaladó ülepedő pormennyiségek, a bányától 1 km-nél távolabb viszont már nem tapasztaltunk határérték túllépést, igaz, a szennyező hatás még 2-3 km távolságban is egyértelműen kimutatható volt. Megállapítást nyert, hogy a meteorológiai viszonyok jelentősen befolyásolják a porszennyezés alakulását. | We examined the soil-pollutant sources in the case of the communal sewage deposition sites in Mikepércs and Újszentmargita. Around these sources we established boreholes with drill-pipes. According to the water and soil samples we stated that although there are differences, in general, similar tendencies can be discovered. We detected significant ammonium and nitrate pollution in both sites, and we found out that the best indicator for the spreading of the pollution is the Na+. The pollution could be evinced in a few hundred meters from the sources. Of the point-sources of the air-pollution we examined the effects of the perlite-mine in Pálháza. We found that there is more remarkable dust-load only in a few hundred meter zone around the mine. In this zone the amount of the settling dust exceeded the hygienic limit, farther than 1 km from the mine there were not higher value than the hygenic limit, but it is true that the pollutant effect could be unambiguously pointed at 2-3 km distance as well. It was proved that the weather condition notably influences the dust pollution

Comparative dosimetrical analysis of intensity-modulated arc therapy, CyberKnife therapy and image-guided interstitial HDR and LDR brachytherapy of low risk prostate cancer

Background: The objective of the study was to dosimetrically compare the intensity-modulated-arc-therapy (IMAT), CyberKnife therapy (CK), single fraction interstitial high-dose-rate (HDR) and low-dose-rate (LDR) brachytherapy (BT) in low-risk prostate cancer. Materials and methods: Treatment plans of ten patients treated with CK were selected and additional plans using IMAT, HDR and LDR BT were created on the same CT images. The prescribed dose was 2.5/70 Gy in IMAT, 8/40 Gy in CK, 21 Gy in HDR and 145 Gy in LDR BT to the prostate gland. EQD2 dose-volume parameters were calculated for each technique and compared. Results: EQD2 total dose of the prostate was significantly lower with IMAT and CK than with HDR and LDR BT, D90 was 79.5 Gy, 116.4 Gy, 169.2 Gy and 157.9 Gy (p < 0.001). However, teletherapy plans were more conformal than BT, COIN was 0.84, 0.82, 0.76 and 0.76 (p < 0.001), respectively. The D2 to the rectum and bladder were lower with HDR BT than with IMAT, CK and LDR BT, it was 66.7 Gy, 68.1 Gy, 36.0 Gy and 68.0 Gy (p = 0.0427), and 68.4 Gy, 78.9 Gy, 51.4 Gy and 70.3 Gy (p = 0.0091) in IMAT, CK, HDR and LDR BT plans, while D0.1 to the urethra was lower with both IMAT and CK than with BTs: 79.9 Gy, 88.0 Gy, 132.7 Gy and 170.6 Gy (p < 0.001). D2 to the hips was higher with IMAT and CK, than with BTs: 13.4 Gy, 20.7 Gy, 0.4Gy and 1.5 Gy (p < 0.001), while D2 to the sigmoid, bowel bag, testicles and penile bulb was higher with CK than with the other techniques. Conclusions: HDR monotherapy yields the most advantageous dosimetrical plans, except for the dose to the urethra, where IMAT seems to be the optimal modality in the radiotherapy of low-risk prostate cancer

Kis és közepes kockázatú prosztatarákos betegek sztereotaxiás sugárkezelése CyberKnife gyorsítóval: korai radiogén mellékhatások

We report implementation of stereotactic body radiotherapy (SBRT) for the treatment of early, localized prostate cancer patients, and acute side effects caused by radiation therapy. Between February 2018 and July 2018, 36 prostate cancer patients were treated with SBRT. Treatments were performed with "CyberKnife M6" linear accelerator. In low-risk patients 8 Gy was delivered to the prostate in each fraction. For intermediate risk, 8 Gy to the prostate and 6.5 Gy to the seminal vesicles were delivered by each fraction with a simultaneous integrated boost technique. A total of 5 fractions (total dose 40 Gy) were given every second working days. Acute radiogenic genitourinary (GU) and gastrointestinal (GI) side effects were assessed using the Radiation Therapy Oncology Group (RTOG) score. The duration of radiotherapy was 1 week and 3 days. The frequency of acute radiogenic side effects was as follows: GU grade 0: 13.9%, grade I: 30.6%, grade II: 52.8%, grade III: 2.7%. GI grade 0: 55.5%, grade I: 30.6%, grade II: 13.9%, grade III: 0%. Grade IV-V side effects were not observed. SBRT appears to be a safe and well tolerated treatment in patients with early stage, localized prostate cancer

Izominvazív hólyagrák képvezérelt sugárkezelése intravesicalisan befecskendezett lipiodolos jelöléssel: A hólyagmegtartó kezelés új lehetősége.

INTRODUCTION AND AIM: To implement lipiodol as a fiducial marker of the tumor bed for image-guided radiotherapy with simultaneous integrated boost technique as part of radiochemotherapy for muscle invasive bladder tumors. METHOD: Since April 2016, radiochemotherapy was performed in 3 male patients with muscle invasive, transitional cell bladder carcinoma. Prior to radiochemotherapy, tumor bed resection was performed for each patient, at the same time 10 ml of lipiodol solution was injected submucosally into the resection site, thus marking the tumor bed for escalated dose irradiation. During radiochemotherapy 51 Gy (1.7 Gy/die) to the pelvis, 57 Gy (1.9 Gy/die) to the whole bladder, and 63 Gy (2.1 Gy/die) to the lipiodol-labeled tumor bed was delivered with simultaneous integrated boost technique. The accuracy of the irradiation was controlled by daily kilovoltage CT. Early radiogenic urogenital and gastrointestinal side effects were recorded according to Radiation Therapy Oncology Group side-effects grading recommendation. RESULTS: Substantial perioperative side effect or toxicity were not observed during and after the injection of lipiodol. The prescribed dose was successfully delivered in all patients. Radiotherapy duration was 6 weeks. The lipiodol-labeled tumor bed was clearly visible on daily kilovoltage cone beam CT. In one patient grade II cystitis and proctitis was observed, another patient experienced only grade I cystitis. These complaints improved with symptomatic medication. In the third patient no significant side effect occurred. CONCLUSIONS: The injection of lipiodol into the bladder wall is a safe technique, without any perioperative toxicity or complication. The tumor bed demarcated by lipiodol was visible both on treatment planning and kilovoltage CTs. The total treatment time was shortened by 4 days. The treatment was well tolerated, early side effects were moderate, or slight. Orv Hetil. 2017; 158(51): 2041-2047