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Found 6278 publications

Fuzzy rulebase parameter determination for stabilized KH interpolation based detection of colorectal polyps on colonoscopy images

Ferenc Lilik Brigita Sziová Raneem Ismail László T. Kóczy Szilvia Nagy

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2020-07-01

Volume: 2020-July

Issue: Unknown

Page Range: Unknown

Description:

In the case of computer aided diagnosis it is advantageous to apply such computational intelligence methods, that can be related to direct measured data by means easily understandable to medical experts. Fuzzy reasoning, if the rulebase is generated from plausible statistical parameters of the image to be analysed, is easy to understand thus can be easily accepted by the society.In the case of colorectal polyps, which might develop into colorectal cancer, thus the population-wide screening would be advisable, more methods are available, but none of them is accepted as standard and effective method. A method based on simple statistical parameters and entropies of image segments is presented, and the effect of determining the rulebase parameters on the efficiency of finding the polyp segment is studied for stabilized Koczy-Hirota rule interpolation.

Open Access: Yes

DOI: 10.1109/FUZZ48607.2020.9177839

Implicit a posteriori error estimation using patch recovery techniques

Tamás L. Horváth Ferenc Izsák

Publication Name: Central European Journal of Mathematics

Publication Date: 2012-02-01

Volume: 10

Issue: 1

Page Range: 55-72

Description:

We develop implicit a posteriori error estimators for elliptic boundary value problems. Local problems are formulated for the error and the corresponding Neumann type boundary conditions are approximated using a new family of gradient averaging procedures. Convergence properties of the implicit error estimator are discussed independently of residual type error estimators, and this gives a freedom in the choice of boundary conditions. General assumptions are elaborated for the gradient averaging which define a family of implicit a posteriori error estimators. We will demonstrate the performance and the favor of the method through numerical experiments. © 2012 Versita Warsaw and Springer-Verlag Wien.

Open Access: Yes

DOI: 10.2478/s11533-011-0119-7

Ultrasonographic assessment of the cervix for prediction of spontaneous preterm birth in singleton pregnancies

Zoltán Papp Zorán Belics

Publication Name: Donald School Journal of Ultrasound in Obstetrics and Gynecology

Publication Date: 2021-01-01

Volume: 15

Issue: 1

Page Range: 49-63

Description:

Spontaneous preterm birth remains a major cause of neonatal morbidity and mortality across the world. Hence, there is an urgent need to find and implement diagnostic methods and interventions that can reduce this public health treat. The ultrasonographic assessment of the cervix is one tool that can be utilized to identify women at increased risk who may be candidates for preventive interventions. There are three main characteristics of the cervix, which can be evaluated during the ultrasound examination of the cervix: cervical length (CL), funneling and cervical gland area. Cervical shortening is one of the first steps in the processes leading to labor and can precede labor by several weeks. Because shortening begins at the internal cervical os and progresses caudally, it is often detected on ultrasound examination before it can be appreciated on physical examination. This is equally true for funneling and cervical gland area (CGA), which cannot be assessed with the physical examination. Based on previous experiences, the timing and frequency of ultrasonographic assessment of the cervix is primarily based on the patient’s prior obstetric history (low-risk women are screened once at 18–24 weeks of gestation; high-risk population usually begins screening at about 16 weeks of gestation and the frequency depends on the measurement result). Classically the diagnosis of short cervix is defined when the CL is less than or equal to 25 mm at these gestational weeks, with the best prediction for PTB obtained at 16–24 weeks of gestation. The CL measurement, evaluation of funneling and CGA together increased the sensitivity of cervical screening for PTB and appeared to be powerful predictor of PTB before 32 weeks gestation. Generally, the importance of positive test is to try to recognize cervical changes on time, to plane the adequate therapy, to prepare for sufficient intrauterine transport, and to administered course of antenatal corticosteroid therapy to women at risk for PTB reduced the incidence and severity of respiratory distress syndrome (RDS) and mortality in offspring. Many interventions (bed rest, lifestyle intervention, cervical cerclage, pessary, progesteron, indomethacin, antibiotics, etc.) have been proposed in an attempt to prevent PTB depending on risk classification.

Open Access: Yes

DOI: 10.5005/jp-journals-10009-1683

Q-Fractional Hesitant Fuzzy Sets and Their Correlation Coefficients: Multi-Criteria Decision Making Technique for Selection of Agricultural Land to Cultivate Apples Crops

Dragan Pamucar Khizar Hayat Nadeem Ajaib Kamran Kausar

Publication Name: IEEE Access

Publication Date: 2025-01-01

Volume: 13

Issue: Unknown

Page Range: 134057-134069

Description:

The q-Fractional Fuzzy Sets (q-FrFSs) offers information in Membership Grade (MG) and Non-membership Grade (NMG) of an object; however, both grades have the hesitancy factor because complex information usually does not give single MG and single NMG. Therefore, in this study we initiate the concept of q-Fractional Hesitant Fuzzy Sets (q-FrHFSs) and its basic properties. In q-FrHFSs not only hesitancy factor is taken into account but it also consider all possible values of uncertainties in {0,1}× {0,1}. Thus Correlation Coefficients (CCs) on q-FrHFSs are necessary to cope uncertain information with hesitancy, MGs and NMGs. In this study we introduce two types of CCs namely CCs on q-FrHFSs and weighted CCs on q-FrHFSs. We investigate underlying properties of these CCs and give a MCDM method on q-FrHFSs environment. We consider an application of our method to agricultural land selection across a set of cities for cultivation of apples crop. At the end, we compare our method of q-FrHFSs to some existing frameworks.

Open Access: Yes

DOI: 10.1109/ACCESS.2025.3582884

Trade-offs in production supply systems

Csaba Tápler Janos Kovacs

Publication Name: International Conference on Industrial Logistics Icil 2012 Conference Proceedings

Publication Date: 2012-01-01

Volume: Unknown

Issue: Unknown

Page Range: 356-361

Description:

The cost price of a final product depends on - among others - the cost of value added processes such as production supply. When planning the supply strategy and defining the parameters of the processes we face a lot of trade-off situations (e.g.: decision between kanban or other supply strategy, kanban quantity, production line loading cycle time, maximal number of picking items on picking lists, etc.). The aim of this paper is to list these decision situations and give adequate solutions on them. By means of mathematical modeling we define the optimal system parameter configuration of a production supply system where the total cost is minimal.

Open Access: Yes

DOI: DOI not available

Long-term effects of the ap-citrox decontamination procedure on the protective oxide-layer formed on stainless steel

D. Oravetz Gábor Patek Bernadett Baja P. Kádár Andrea Szabó Nagy Varga Kálmán Dezso Varga József Tóth Zoltán Németh István Cserny László Kövér Schunk János Z. Homonnay E. Kuzmann

Publication Name: Korrozios Figyelo

Publication Date: 2007-07-09

Volume: 47

Issue: 3

Page Range: 62-72

Description:

Our previous studies have revealed that a "hybrid" structure of the amorphous and crystalline phases is formed in the outermost surface region of the austenitic stainless steel tubes of steam generators (SGs) as an undesired consequence of the industrial application of the AP-CITROX decontamination technology. The formation of this mobile oxide-layer increased the amount of the corrosion products in the primary circuit significantly (∼80 kg/block), resulting in magnetite deposition on fuel assemblies. As deposits blocked the cooling channels, the flow rate of water coolant through the reactor core decreased. Consequently, the power capacity of three nuclear reactor units had to be reduced, and full core fuel replacement became necessary. In the light of the above events, the present work gives a brief overview on the general corrosion state of the heat exchanger tubes of SGs, concerning the long-term effects of the AP-CITROX procedure on the chemical composition and structure of the protective oxide-layer. Owing to the fact that there is no investigation method available for the in-situ monitoring of the inner surfaces of heat exchanger tubes, a research project based on sampling as well as on ex-situ electrochemical and surface analytical measurements was elaborated. Within the frame of this project, comprehensive investigation of the general corrosion state and metallographic features of 36 stainless steel specimens, cut out from various locations of the four steam generators of the Paks NPP has been performed. Electrochemical (voltammetric) and surface analytical (SEM-EDX, CEMS, and XRD) results reveal that some beneficial changes in the corrosion properties, morphology and chemical composition of the inner surfaces of heat exchanger tubes can be observed in the time period of 2000-2006.

Open Access: Yes

DOI: DOI not available

Effect of biodiesel-derived by-product on the germination of common ragweed (Ambrosia artemisiifolia L.) in pot experiments

Károly Pocsai Péter Csontos

Publication Name: Journal of Landscape Ecology

Publication Date: 2012-01-01

Volume: 10

Issue: 2

Page Range: 341-349

Description:

The effect of biodiesel-derived by-product (SZO = soap-like emulsion) from rape oil was examined on the germination of common ragweed (Ambrosia artemisiifolia L.) achenes in pot experiments. Soils were treated in three different doses: 2500, 5000 and 10000 liter/ha, applied in proportion to the surface area of the pots. Control soil was moistened with the same amount of tap water. Fifty ragweed achenes were sown into each pot, then the pots were placed in a refrigerator for cold treatment (35 days, +7 °C). Following cold treatment the pots were placed in an unheated greenhouse and the germination of ragweed achenes were monitored for 40 days. Common ragweed seedlings emerged from soils of each treatment including the control, but their rate of germination differed. The highest number of seedlings appeared in the control pots (51.5%), whereas the lowest number was observed in the 2500 l/ha dose pots (33.0%). Order of the treatments according to increasing germination succes was the following: 2500 < 10000 < 5000 < control. Germination rate in treatments 2500 l/ha and 10000 l/ha was significantly lower than it was detected in the control. SZO dose of 5000 l/ha resulted intermediate germination rate of ragweed achenes, that did not differ significantly from any other treatments. Based on the results, the studied biodiesel-derived by-product can potentially be used in weed control. For its appropriate use, the effective chemical components of the SZO should be identified. Further studies needed to determine the optimal dose applicable in field management and to investigate the potential effect of SZO on the germination of cultivated species.

Open Access: Yes

DOI: 10.56617/tl.3793

Structural behavior of built-up I-shaped CFS beams

Ardalan B. Hussein Diyari B. Hussein

Publication Name: Results in Engineering

Publication Date: 2024-12-01

Volume: 24

Issue: Unknown

Page Range: Unknown

Description:

The use of back-to-back built-up C-section beams is becoming increasingly common in CFS construction due to their cost-effectiveness and enhanced load-carrying capacity, making them suitable for longer beam spans and convenient for transportation. These built-up sections are utilized in wall studs, truss components, and floor joists, with intermediate screw fasteners placed at specific intervals to prevent the separate bowing of channels. This study reveals a ratio of 1.003 between experimental findings and finite element analysis results, and 1.002 between experimental findings and direct strength method results, indicating a strong correlation between experimental data from nonlinear finite element analysis and predictions based on the American Iron and Steel Institute and Australian and New Zealand Standards, particularly in predicting the flexural buckling strength of beam specimens. Furthermore, ongoing research is investigating the impact of screw spacing on flexural strength. This study presents results from 175 finite element tests, evaluating seven distinct cross-sections with twelve unique screw spacings. These spacings correspond to the half wavelength of local, distortional, and global buckling, divided by values from one to four. It was found that screw spacing based on half the local buckling half-wavelength along the centerline of the webs increased the critical global buckling moment capacity and the nominal flexural strength by 56 % and 27 %, respectively. For double-lane screws with the same spacing, these increases were even more substantial, reaching 65 % and 31 %, respectively. Economically, the recommended spacing for single-lane screws is half the local buckling half-wavelength.

Open Access: Yes

DOI: 10.1016/j.rineng.2024.102963

Municipal bonds in Hungary: Constraints and challenges

Kovács Gábor

Publication Name: Springer Geography

Publication Date: 2015-01-01

Volume: Unknown

Issue: Unknown

Page Range: 257-274

Description:

After the collapse of communist rule, Hungarian local governments had to meet new challenges and expectations. Due to the decentralisation process, local governments’ revenues decreased significantly in the last two decades, while the level and scope of services provided decreased less rapidly, if at all. Consequently, local governments, short of resources, had to develop their ability to raise funds needed to meet local spending needs. This study examines the general theoretical framework of municipal borrowing, comparing the economic and social advantages of bank loans versus municipal bonds. It also evaluates the role of the national government’s central administration in regulating local authority indebtedness. It then presents and analyses the characteristics of Hungarian local government bond financing, assessing the appropriateness of bonds as a local government fundraising tool. The indebtedness of Hungarian local authorities has increased drastically since 2006, mainly through bond financing. A substantial proportion of these bonds were issued in foreign currencies because interest rates were lower. The subsequent economic downturn and devaluation of the Hungarian forint has left many local governments worse off because their indebtedness has increased in forint terms. Bond financing is often considered simply an alternative form of borrowing, and Hungarian local governments do not fully benefit from the flexible features offered by bonds. In today’s Hungary, bond financing offers opportunities to broaden local government financial freedom and reduce the financial risk related to borrowing, but they also pose risks, particularly in the absence of local expertise. Regulation of local government borrowing is still mainly based on the coercive effect of a credit limit. This is a one-sided approach to the problem, and current Hungarian regulations fail to meet the expectations of the most important players in the European capital market, namely, institutional investors. New regulations are needed which can enhance the beneficial characteristics of bonds, while preserving the security they provide to local governments and prospective investors.

Open Access: Yes

DOI: 10.1007/978-94-007-5503-1_13