Academic literature on the topic 'Combinative distance-based assessment'

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Journal articles on the topic "Combinative distance-based assessment"

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Hernandez, Cesar, Diego Giral, and Tania Vaca. "Performance evaluation of a proposal for spectrum assignment based on combinative distance-based assessment multicriteria strategy." International Journal of Electrical and Computer Engineering (IJECE) 14, no. 5 (2024): 5308. http://dx.doi.org/10.11591/ijece.v14i5.pp5308-5318.

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Cognitive radio networks offer an alternative to low spectral availability in some frequency bands due to their high demand for frequency channels. This article proposes to improve the spectral assignment based on the combinative distance-based assessment multicriteria algorithm. The metrics obtained are compared with a simple additive weighting algorithm and a RANDOM selection. To establish the algorithm 's performance, five quality-of-service metrics are used: number of handoffs, number of failed handoffs, average bandwidth, average throughput, and cumulative average delay. From the analysis of the results obtained, combinative distance-based assessment (CODAS) presented the best result for the cost metrics with the lowest levels, and for the benefit metrics, the highest levels were obtained.
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Agwa, Ahmed. "Siting hydropower plant by rough set and combinative distance-based assessment." PRZEGLĄD ELEKTROTECHNICZNY 1, no. 3 (2021): 17–22. http://dx.doi.org/10.15199/48.2021.03.03.

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Seker, Sukran. "A novel interval-valued intuitionistic trapezoidal fuzzy combinative distance-based assessment (CODAS) method." Soft Computing 24, no. 3 (2019): 2287–300. http://dx.doi.org/10.1007/s00500-019-04059-3.

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Prasetyo, Tejo Dwi, Fatma Agus Setyaningsih, and Suhardi Suhardi. "Sistem Seleksi Penerima Bantuan Program Keluarga Harapan Menggunakan Metode Combinative Distance-Based Assessment (CODAS) di Kecamatan Pontianak Timur." Coding Jurnal Komputer dan Aplikasi 9, no. 03 (2022): 339. http://dx.doi.org/10.26418/coding.v9i03.50467.

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Program Keluarga Harapan merupakan salah satu upaya pemerintah dalam menanggulangi masalah kemiskinan di Indonesia. Program ini memberikan bantuan tunai dan non-tunai kepada Rumah Tangga Sangat Miskin (RTSM), yang memenuhi kriteria dan persyaratan bagi penerima bantuan PKH. Agar penyaluran bantuan sosial ini dapat berjalan lancar dan tepat sasaran, dalam penelitian ini dirancang dan dibangun sebuah sistem yang bisa membantu pengambil keputusan dalam mengolah data yang memiliki banyak kriteria, atau yang sering disebut dengan istilah Multi-Criteria Decision Making (MCDM). Metode Combinative Distance-Based Assessment (CODAS) adalah salah satu metode MCDM yang menggunakan pengukuran jarak Euclidean dan Taxicab alternatif dari solusi ideal-negatif. Dalam penelitian ini metode CODAS berhasil diterapkan dalam sistem untuk memberikan rekomendasi calon penerima bantuan PKH, dengan hasilnya adalah 20 dari 200 peserta dinyatakan masuk desil 1 di mana 17 di antaranya dinyatakan lolos seleksi penerima bantuan PKH oleh sistem. Kata Kunci : Program Keluarga Harapan, Multi Criteria Decision Making, Combinative Distance-Based Assessment
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Kumar, Sunil, Sandeep Kumar Gautam, Ankush Kumar, Rajesh Maithan, and Anil Kumar. "Sustainability assessment of different nanoparticle for heat exchanger applications: an intuitionistic fuzzy combinative distance-based assessment method." Acta Innovations, no. 40 (September 30, 2021): 44–63. http://dx.doi.org/10.32933/actainnovations.40.4.

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The rate at which the conventional energy sources are depleting is a matter of concern, and there have been major attention on this to make the thermal systems environment friendly, efficient, economic, sustainable, technically reliable. Sustainability of five different types of nanoparticles (Ceramic, carbon based, metal based, polymeric, and lipid based) from the perspective of four aspects involving cost, efficiency, technicality and environmental effect, in heat exchangers has been assessed. The analysis is carried out using the intuitionistic fuzzy combative distance based assessment (IFCODAS) method. In order to measure the sustainability of nanoparticles, a set of eleven evaluating criteria have been accredited on the basis of expert opinions and focus group meetings. By amalgamating the intuitionistic fuzzy set (IFS) theory as well as the use of distance-based assessment (CODAS) method, the IFCODAS method has permitted the decision-makers to rate the alternative five nanoparticles pertaining to each criterion. On the basis of the results obtained from IFCODAS method, it is observed that the carbon based nanoparticles have an immense potential to provide significantly reliable and sustainable thermal system than other nanoparticles.
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Biswas, Sanjib, and Dragan Pamucar. "Combinative distance based assessment (CODAS) framework using logarithmic normalization for multi-criteria decision making." Serbian Journal of Management 16, no. 2 (2021): 321–40. http://dx.doi.org/10.5937/sjm16-27758.

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The purpose of this paper is to present an extended Combinative Distance based Assessment (CODAS) framework using logarithmic normalization (LN) scheme. LN is useful in the situations where criteria values differ significantly. This framework is used to carry out a comparative performance based ranking of the popular smartphones in India. The result obtained from this extended version of CODAS method (CODAS-LN) shows consistency with that generated by using some other established multi-criteria decision making (MCDM) approaches. The sensitivity analysis shows considerable stability in the result. Further, it is observed that CODAS-LN is free from rank reversal phenomenon and follows the transitivity property. Findings of the case study suggest that the smartphones with higher computational capability and features rank in top brackets.
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Suriati, Neneng, Dwi Marisa Midyanti, and Uray Ristian. "Implementasi Metode Combinative Distance-Based Assessment (CODAS) Untuk Rekomendasi Rekanan Jasa Konsultansi Berbasis Website." JURIKOM (Jurnal Riset Komputer) 9, no. 5 (2022): 1632. http://dx.doi.org/10.30865/jurikom.v9i5.4947.

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Regional Research, Development and Innovation (PPID) is one of the fields in the Planning, Development, Regional, Research and Development Agency (BAPPEDALITBANG). The PPID sector at the Kubu Raya Regent's Office has a program to select consulting services. However, the implementation of the selection of consulting services is still done manually by giving each participant a score based on predetermined criteria and the files that have been collected. These values are then added up manually and ranked. The basis for assigning value to participants in consulting services needs to be managed so that the assessment is more effective and structured. Storage of administrative files is still in the form of hard files, so it is less effective because it results in several risks, such as file loss and difficulty in searching for files, if needed. This study builds a decision support system using the Combinative Distance-Based Assessment (CODAS) method to recommend consulting service partners. The application of the CODAS method uses 3 criteria, 6 sub-criteria, and 19 sub-criteria. The results of calculations using the CODAS method are sorted from the highest value to the lowest value. From the 30 alternative data used, the first rank is A1 with a value of 4.6217, the second rank is A23 with a value of 4.3527, and the third rank is A27 with a value of 4.2107. Of the 30 alternative data used, the Spearman rank correlation value of 0.9973 is included in the very high positive category
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Ecer, Fatih, Dragan Pamucar, Abbas Mardani, and Melfi Alrasheedi. "Assessment of renewable energy resources using new interval rough number extension of the level based weight assessment and combinative distance-based assessment." Renewable Energy 170 (June 2021): 1156–77. http://dx.doi.org/10.1016/j.renene.2021.02.004.

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Akmal Siahaan, Munawir. "Sistem Pendukung Keputusan Penilaian Kinerja Pegawai Negeri Sipil Menggunakan Metode (Combinative Distance – Based Assessment) Pada Kantor Camat Sei Kepayang." Bulletin of Information Technology (BIT) 3, no. 3 (2022): 195–205. http://dx.doi.org/10.47065/bit.v3i3.336.

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Performance appraisal is carried out to evaluate the performance of existing employees and can also be used by agencies to spur employees to work better, so an agency can give awards to employees who are considered to be outstanding. Awards can be in the form of awards, appointments in positions, promotion, or others, which can give enthusiasm and motivation to employees. The system that runs in the Sei Kepayang sub-district office still has weaknesses, namely the employee appraisal process is still done manually and there is also no system for decision-making that supports employee performance appraisal. In solving these problems, the researcher uses the method (combinative distance-based assessment) which is useful for calculating employee performance appraisals, so that the method (combinative distance-based assessment) can find out which employees get the highest achievement score. while the program to create the system uses a visual basic program. This application will display performance appraisals automatically and the final report can be printed directly, by month and year. This study aims to produce applications that become supporting facilities as a tool for calculating employee performance more effectively
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Aziz, Alber S. "Neutrosophic Combinative Distance-based Assessment (CODAS) Method for Evaluating the Financial and Operational Performance of Shipping Companies." International Journal of Advances in Applied Computational Intelligence 4, no. 1 (2023): 28–36. http://dx.doi.org/10.54216/ijaaci.040103.

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Stakeholders must evaluate the efficiency, profitability, risk management, and overall operational effectiveness of shipping businesses by analyzing their financial and operational performance. Revenue, expenses, fleet utilization, accident rates, market share, and competitive advantage are only a few of the parameters that must be analyzed in this procedure. Stakeholders may use this information to make better choices, spot weak spots, and measure up to competitors. An overview of the criteria used to evaluate the financial and operational performance of shipping businesses is provided in this paper, together with an emphasis on the importance of such assessments in enabling strategic decision-making and long-term development within the shipping sector. This paper used the neutrosophic set framework to overcome the uncertain data. The neutrosophic set combined with the combinative distance-based assessment (CODAS) method to evaluate the financial and operational performance of shipping companies. There are ten criteria and eight companies are used in this study. The application shows the results of the proposed method.
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Book chapters on the topic "Combinative distance-based assessment"

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Chakraborty, Shankar, Prasenjit Chatterjee, and Partha Protim Das. "Combinative Distance-Based Assessment (Codas) Method." In Multi-Criteria Decision-Making Methods in Manufacturing Environments. Apple Academic Press, 2023. http://dx.doi.org/10.1201/9781003377030-17.

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Van Duong, Binh, Igor K. Fomenko, and Kien Trung Nguyen. "Fractal-Based Evaluation of the Spatial Relationship Between Conditioning Factors and the Distribution of Landslides (a Case Study in Tinh Tuc, Cao Bang Province, Vietnam)." In Progress in Landslide Research and Technology. Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-44296-4_13.

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AbstractThis paper presents the assessment results of the spatial relationship between past landslides and four landslide factors in Tinh Tuc town, Cao Bang province, Vietnam, including distance to roads, distance to faults, distance to drainage, and distance to geological boundaries. The fractal dimension values were determined using fractal analyses on three sets of raw data, including the number of landslides, landslide density, and landslide relative density. Using a combination of the frequency ratio (FR) method and the fractal method, landslide susceptibility maps were produced to determine which raw data set more properly analyzes the role of factors in the development of the landslide process. Assessment results using the receiver operating characteristic (ROC) method indicate that the fractal analysis of the raw data sets successfully determines the spatial relationship between conditioning factors and landslides in the study area. In addition, relationship analyses using datasets based on landslide density provide more optimal outcomes. The authors also suggest integrating the fractal method with other quantitative assessment methods to improve the accuracy of landslide prediction in Vietnam and worldwide.
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Verginelli, Iason. "Petroleum Vapor Intrusion." In Advances in the Characterisation and Remediation of Sites Contaminated with Petroleum Hydrocarbons. Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34447-3_6.

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AbstractPetroleum vapor intrusion (PVI) is the process by which volatile petroleum hydrocarbons released from contaminated geological materials or groundwater migrate through the vadose zone into overlying buildings. PVI science showed that petroleum hydrocarbons are subjected to natural attenuation processes in the source zone and during the vapor transport through the vadose zone. Specifically, in the presence of oxygen, aerobic biodegradation typically reduces or eliminates the potential for PVI. This behavior justifies the different approach usually adopted for addressing PVI compared to less biodegradable compounds such as chlorinated solvents. In some countries, it was introduced the concept of vertical exclusion distance criteria, i.e., source to building distances above which PVI does not normally pose a concern. For buildings where the vertical separation distance does not meet screening criteria, additional assessment of the potential for PVI is necessary. These further investigations can be based on modeling of vapor intrusion, soil gas sampling, indoor measurements or preferably a combination of these to derive multiple lines of evidence. The data collected are then used for a risk assessment of the vapor intrusion pathway. This chapter provides an overview of state-of-the-science methodologies, models, benefits and drawbacks of current approaches, and recommendations for improvement.
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Marjanović, Miloš, Biljana Abolmasov, Jelka Krušić, and Uroš Đurić. "Regional Debris Flow Hazard Assessment of the Grdelica Gorge (Serbia)." In Progress in Landslide Research and Technology, Volume 3 Issue 1, 2024. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-55120-8_15.

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AbstractRoad infrastructure development is currently very intensive in Serbia. One such example is the Grdelica Gorge, where a new highway was aligned and put into service in 2019. The Gorge has provided a very challenging engineering environment imposing high levels of several hazard types: floods; slides; debris flows; and rockfalls. In this work, the debris flow hazard for the first 15 km of the road route was in focus. The assessment included an expert-driven analysis for identifying potential source areas, coupled with deterministic modelling of the flowing process originating from these source areas, resulting in detailed simulations of the final runout distance, height of deposit, and flow velocity, which are all reliable parameters for mitigating the hazard across the road alignment. A combination of geomorphological criteria, processed in a GIS environment was used to narrow down the search of source areas containing loose, erodible material which easily mobilizes under saturated conditions. The criteria were calibrated by the outlines of the available inventory, acquired by remote sensing techniques. The Digital Terrain Model with 12.5 m resolution was used for running RApid Mass Movement Simulation (RAMMS), using estimated bulk density and friction coefficients as input parameters. Since there was no recent debris flow in the area for the appropriate back-analysis of these parameters, experience-and lab-based estimations were used. Several simulations have reached the road alignment, wherein a few imposed significant threats with respect to deposit height and velocity that require additional attention.
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"Chapter 7 Combinative distance-based assessment (CODAS) for decision-making." In Multiple Criteria Decision-Making Methods. De Gruyter, 2022. http://dx.doi.org/10.1515/9783110743630-007.

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Mishra, Partha Sarathi, and Soumi Muhuri. "Evaluation of Architectural Heritage by Various Multi-Criteria Decision-Making Analysis." In Advances in Religious and Cultural Studies. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-6701-2.ch018.

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Selection of the architectural heritage (AH) for conservation considers many dimensions and parameters, which is a multitasking process. Many parameters can be valued directly, while others indirectly. The process of evaluation should be robust for all decision-makers. As such, the multi-criteria decision-making (MCDM) process seems apt. This research evaluates various MCDM methods using Odishan temple architecture as the case study. Five dimensions as architectural and aesthetic value, economic value, environmental and ecological value, historical value, and socio-cultural value have been identified. The selected MCDM methods are weighted sum method, weighted product method, weighted aggregated sum product assessment, evaluation based on distance from average solutions, techniques for the order of preference by similarity to ideal solutions, additive ratio assessment, complex proportional assessment, combinative distance-based assessment, and VIKOR. This study compares different MCDA methods for the best AH using different dimensions.
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Conference papers on the topic "Combinative distance-based assessment"

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Park, Jungseo, Seunghwan Mun, Chungmin Hyun, Byungkwon Kang, and Kwanghee Ko. "Similarity Assessment Method for Automated Curved Plate Forming." In SNAME 5th World Maritime Technology Conference. SNAME, 2015. http://dx.doi.org/10.5957/wmtc-2015-240.

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In this paper, a novel similarity estimation method for two shapes in the automated thermal forming is proposed. One shape is given as a CAD surface, and the other is given as a set of points measured points. These two shapes are registered with respect to a reference coordinate system so that they are aligned as closely as possible using the ICP based method. Three geometric properties are considered in the method. The first property is the distance between them. At each measured point, the closest distance to the CAD surface is computed, and the defined tolerance for the distances is used as a similarity measure. The second measure is the average distance of the minimum distances to the CAD surface at the measured points. The third one is the average of the bending strain values at the measured points and at the points on the CAD surface that are orthogonal projection points of the measured ones. The proposed similarity is computed as the linear combination of the three properties with weight values, which are determined empirically. Extensive experiments show that the proposed similarity method successfully computes the similarity of a plate to its CAD shape in the forming process.
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Lee, Myeong-Woo, Kunio Hasegawa, and Yun-Jae Kim. "Proposal of New Combination Criterion for Pipe With Circumferential Multiple Cracks Based on Ductile Failure Simulation." In ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-84822.

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In this paper, the combination rule for circumferential multiple-cracked pipe assessment is investigated using finite element damage analysis. The FE damage analysis based on the stress-modified fracture strain model is validated against limited fracture test data of two circumferential surface cracked pipes. Then systematic parametric study is performed using FE damage analysis for symmetrical surface cracked pipes. Failure bending stresses are calculated using the combination rule and the net-section collapse load approach for single crack provided in ASME BPV Code. It is found that predicted failure bending stress using the combination rule might be non-conservative when the distance between two cracks is short. To overcome the problem, a new combination criterion based on crack dimensions is proposed and compared with numerical data.
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LiangLiang Tao, He Lin, YongJun Shen, and GuiDong Zhang. "Optimal combination between subjective weighting and objective weighting based on maximum square sum of distance for information security risk assessment." In 2016 7th IEEE International Conference on Software Engineering and Service Science (ICSESS). IEEE, 2016. http://dx.doi.org/10.1109/icsess.2016.7883111.

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Huh, Nam-Su, Suhn Choi, Keun-Bae Park, Jong-Min Kim, Jae-Boong Choi, and Young-Jin Kim. "Guidance on a Defect Interaction Effect for In-Plane Surface Cracks Using Elastic Finite Element Analyses." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61405.

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The crack-tip stress fields and fracture mechanics assessment parameters, such as the elastic stress intensity factor and the elastic-plastic J-integral, for a surface crack can be significantly affected by adjacent cracks. Such a defect interaction effect due to multiple cracks can magnify the fracture mechanics assessment parameters. There are many factors to be considered, for instance the relative distance between adjacent cracks, crack shape and loading condition, to quantify a defect interaction effect on the fracture mechanics assessment parameters. Thus, the current guidance on a defect interaction effect (defect combination rule), including ASME Sec. XI, BS7910, British Energy R6 and API RP579, provide different rules for combining multiple surface cracks into a single surface crack. The present paper investigates a defect interaction effect by evaluating the elastic stress intensity factor of adjacent surface cracks in a plate along the crack front through detailed 3-dimensional elastic finite element analyses. The effects of the geometric parameters, the relative distance between cracks and the crack shape, on the stress intensity factor are systematically investigated. As for the loading condition, only axial tension is considered. Based on the elastic finite element results, the acceptability of the defect combination rules provided in the existing guidance was investigated, and the relevant recommendations on a defect interaction for in-plane surface cracks in a plate were discussed.
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Heckmann, Gerardo. "Remix technics with exe learning to improve statistics learning using moodle." In Advances in Statistics Education: Developments, Experiences, and Assessments. International Association for Statistical Education, 2015. http://dx.doi.org/10.52041/srap.15706.

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If there is an issue that is particularly hard to understand for students in statistical inference that is the concept of the distribution of a combination of random variables: an estimator. In a massive, 300 or more students’ classroom, the challenge is even greater. This situation is common at the Faculty of Economics of the National University of Córdoba (FCE- UNC), Argentina, with more than 12,000 students. The purpose of this work is to show how to take advantage from the production of Scorm materials that facilitate the integration of resources available on the web to improve the study of statistical issues in mass classrooms through the interaction with Moodle platform. Based on Exe Learning, an SCORM was developed. This is an interactive material to complement the study of Sampling Distributions. Includes sections designed to ensure understanding of the concepts, based on the use of simulators from the Rice University and auto evaluation questions. You may visit the site at: http://aulas.eco.unc.edu.ar/course/view.php?id=7 Implemented in a course of statistical inference at FCE-UNC it seems to be a very good alternative in the search for high degree of personalization in the interaction with the students, despite the massiveness of the number of attendees. A personal score is assigned on the base of the student interaction with the Scorm and registered in Moodle. Feedback is automatically generated while using the app (correct answers are stimulated with Genial! Well done!, etc. and those wrong with clues to get to the correct answer and an expression of encouragement: Try again! It is important to remark that this kind of materials also seem to be an excellent tool to motivate teachers (materials production) and students (Statistics education in the age of social networking and distance education). Also are intended to close the gap in advancing Statistical education using technology and mobile devices.
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Bouydo, Afaf, Pierre Dulieu, Valéry Lacroix, Kunio Hasegawa, and Vratislav Mares. "A Comparison of Proximity Rules for Surface Planar Flaws." In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93513.

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Abstract Flaw assessment according to Fitness-For-Service (FFS) codes is usually based on equations describing the impact of a single flaw in piping or pressure vessels components. However, when multiple flaws are detected, combination rules are to be taken into account to evaluate whether these flaws should be combined into a larger flaw or should be evaluated as separate ones. In recent years, numerous works have been done to evaluate the conservatism of the combination rules required by FFS codes and, if needed, establish new characterization rules. These new characterization rules are based on the distance between flaws, their depths, their lengths or a combination of these three parameters in order to reflect the level of interaction between adjacent flaws. A comparison, focusing on multiple surface planar flaws, between ASME B&PV Section XI current combination rules, other Fitness-For-Service codes and other combination rules established by fellow authors is presented in this paper.
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Kamaya, Masayuki. "A Plastic Collapse Assessment Procedure for Multiple Cracks Under Internal Pressure." In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57584.

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The influence of the interaction between two surface cracks on the limit pressure was examined by finite element analysis. Longitudinal semi-elliptical surface cracks were assumed to be on a straight pipe that was subjected to internal pressure. The changes in limit pressure due to the relative spacing of cracks and the geometries of the cracks and pipe were investigated. The intensity of the interaction depended on the relative distance between the cracks as well as the pipe and crack geometries. In all cases, the maximum magnitude of the reduction in limit pressure was equivalent to twice the crack face area. Based on the results obtained, criteria for the combination rules the for plastic collapse analysis were proposed. Furthermore, it was concluded that the surface length of the combined cracks could be assumed to be equal to the sum of their lengths. The ligament length was not included.
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Dulieu, Pierre, Valéry Lacroix, Kunio Hasegawa, Yinsheng Li, and Bohumir Strnadel. "Alternative Characterization Rules for Multiple Surface Planar Flaws." In ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-84960.

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When multiple surface flaws are detected in pressure components, their potential interaction is to be assessed to determine whether they must be combined or evaluated independently of each other. This assessment is performed through the flaw characterization rules of Fitness-For-Service (FFS) Codes. However, the specific combination criteria of surface flaws are different among the FFS Codes. Most of the time, they consist of simple criteria based on distance between flaws and flaw depth. This paper aims at proposing alternative characterization rules reflecting the actual level of interaction between surface planar flaws. This interaction depends on several parameters such as the relative position of flaws, the flaw sizes and their aspect ratio. Thanks to numerous three-dimensional XFEM simulations, best suited combination criteria for surface planar flaws are derived by considering the combined influence of these parameters.
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Zhou, Jiao, Xingyu Peng, and Dongchi Yao. "Quantitative Risk Assessment Techniques Based on Uncertainty Theory for Natural Gas Distribution Station." In 2018 12th International Pipeline Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/ipc2018-78260.

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Pipeline stations, as an important part of long-distance pipeline systems, include lots of facilities which are highly concentrated and always operate continuously. Risk assessment is an important foundation work for the risk management of these stations. Since various uncertainties exist during the quantitative risk assessment (QRA), this paper explores the theories and approaches of QRA for station accidents, and also introduces some specific mathematical theories for quantification and dealing with uncertainties. This paper combines uncertainty theory effectively with the QRA for gas distribution stations, analyzes the uncertain factors in the QRA of gas distribution station, and establishes Bayesian update model for estimating basic events’ failure rates and probabilities of failure on demand based on generic failure data and plant-specific data. And it also offers conversion method among conjugate prior distribution of different types. Besides, probabilistic estimation model is set up by the combination of fuzzy set theory, expert judgments and fuzzy group decision making. The paper builds Fuzzy Bow-Tie quantitative model for distribution station under dependency relationships, and proposes the sensitivity analysis method for the accident model based on fuzzy importance index, fuzzy uncertainty index and minimal cut sets importance index.
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Garcia-Hernandez, Augusto, and Shane Siebenaler. "Acoustic Leak Detection Technology Assessment." In 2012 9th International Pipeline Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ipc2012-90146.

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Leak detection systems are a vital part of a pipeline integrity management program. For liquid hydrocarbon pipelines, these leak detection systems can take the form of measuring conditions inside the pipeline (internal detection) or by use of hardware installed outside of the pipe (external detection). One internally-based technology is acoustic leak detection, sometimes known as rarefaction-wave monitoring. This technology is based on detecting transient pressure waves that are generated when a sudden leak occurs. Acoustic pressure waves travel in the pipeline at the speed of sound of the fluid that is being transported and can be detected by dynamic pressure sensors. Various filters and algorithms can be used to identify this disturbance and distinguish it from other pressure events on the pipeline. This architecture can even be used for noise and for signal pattern recognition to allow for automatic alarming of potential leak events. Each manufacturer of such technology applies unique algorithms or processing methods to capture and analyze the pressure signals that are used to later predict leaks and their locations. This paper presents a comprehensive review of the technical basis and methodology employed by acoustic leak detection systems in order to further understand their capabilities and limitations. This work included a vast amount of hydraulic modeling aimed at understanding the physics of wave propagation caused by leak events. Diverse parameters, such as initial pressure wave amplitude, signal attenuation, flow and pressure dependence, speed of sound effects, and sensor locations were evaluated. This modeling was conducted for a variety of simulated fluids. A proportional relationship between leak rate and the initial pressure disturbance caused by a leak was obtained. This linear trend can be used in combination with an attenuation model to calculate sensor location limitations. The work determined that the uncertainty in the speed of sound for a pipeline fluid segment significantly impacts the error bands of leak location. The modeling was used to generate correlations for signal attenuation over distance as a function of pipeline conditions.
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Reports on the topic "Combinative distance-based assessment"

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Bäumler, Maximilian, Günther Prokop, Matthias Lehmann, and Linda Dziuba-Kaiser. Use Information You Have Never Observed Together: Data Fusion as a Major Step Towards Realistic Test Scenarios. TU Dresden, 2020. http://dx.doi.org/10.26128/2024.3.

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Scenario-based testing is a major pillar in the development and effectiveness assessment of automated driving systems. Thereby, test scenarios address different information layers and situations (normal driving, critical situations and accidents) by using different databases. However, the systematic combination of accident and / or normal driving databases into new synthetic databases can help to obtain scenarios that are as realistic as possible. This paper shows how statistical matching (SM) can be applied to fuse different categorical accident and traffic observation databases. Hereby, the fusion is demonstrated in two use cases, each featuring several fusion methods. In use case 1, a synthetic database was generated out of two accident data samples, whereby 78.7% of the original values could be estimated correctly by a random forest classifier. The same fusion using distance-hot-deck reproduced only 67% of the original values, but better preserved the marginal distributions. A real-world application is illustrated in use case 2, where accident data was fused with over 23,000 car trajectories at one intersection in Germany. We could show that SM is applicable to fuse categorical traffic databases. In future research, the combination of hotdeck- methods and machine learning classifiers needs to be further investigated.
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2

van Gemert, Rob, Per Holliland, Konrad Karlsson, Niklas Sjöberg, and Torbjörn Säterberg. Assessment of the eel stock in Sweden, spring 2024 : fifth post-evaluation of the Swedish eel management. Department of Aquatic Resources, Swedish University of Agricultural Sciences, 2024. http://dx.doi.org/10.54612/a.4iseib7eup.

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For decades, the population of the European eel has been in severe decline. In 2007, the European Union decided on a Regulation establishing measures for the recovery of the stock, which obliged Member States to implement a national Eel Management Plan by 2009. Sweden submitted its plan in 2008. According to the Regulation, Member States shall report regularly to the EU-Commission, on the implementation of their Eel Management Plans and the progress achieved in protection and restoration. The current report provides an assessment of the eel stock in Sweden as of spring 2024, intending to feed into the national reporting to the EU in August this year. This report updates and extends previous evaluation reports by Dekker (2012, 2015) and Dekker et al. (2018, 2021). In this report, the impacts on the stock - of fishing, restocking and mortality related to hydropower generation - are assessed. Other anthropogenic impacts (climate change, pollution, increased impacts of predators, spread of parasites, disruption of migration due to disorientation after transport, and so forth) probably have an impact on the stock too, but these factors are hardly quantifiable, and no management targets have been set. For that reason, and because most factors were not included in the EU Eel Regulation, these other factors are not included in this report. Our focus is on the quantification of silver eel biomass escaping from continental waters towards the ocean (current, current potential and pristine) and mortality risks endured by those eels during their whole lifetime. The assessment is broken down on a geographical basis, with different impacts dominating in different areas (west coast, inland waters, Baltic coast). In the last decade, a break in the downward trend in glass eel recruitment has been observed, with recruitment no longer declining consistently. Whether that relates to recent protective actions, or is due to other factors, is yet unclear. Nevertheless, recruitment levels remain at historically low levels. This report contributes to the required international assessment, but does not discuss the causing factors behind the recent recruitment trend and the overall status of the stock across Europe. For the different assessment areas, results summarise as follows: On the west coast, a commercial fyke net fishery on yellow eel was exploiting the stock, until this fishery was completely closed in spring 2012. A fishery-based assessment no longer being achievable, we present trends from research surveys (fyke nets). Insufficient information is currently available to assess the recovery of the stock in absolute terms. Obviously, current fishing mortality is zero (disregarding the currently unquantifiable effect of illegal fishing), but none of the other requested stock indicators (current, current potential and pristine biomass) can be presented. The formerly exploited size-classes of the stock show a recovery in abundance after the closure of the commercial fishery, and the smaller size classes show a break in their decline in line with the recent global trend of glass eel recruitment. In order to support the recovery of the stock, or to compensate for anthropogenic mortality in inland waters, young eel has been restocked on the Swedish west coast since 2010. Noting the quantity of restocking involved, the expected effect (ca. 50 t silver eel) is relatively small, and hard to verify – in comparison to the potential natural stock on the west coast (an order of 1000 t). However, for the currently depleted stock, the contribution will likely constitute a larger share of silver eel escapement. For inland waters, this report updates the 2021 assessment, with substantial changes in methodology being the use of a new natural recruitment model, and the full separation of Trap & Transport catches from the fisheries statistics. The assessment for the inland waters relies on a reconstruction of the stock from information on the youngest eels in our waters (natural recruits, assisted migration, restocking). Based on 78 years of data on natural recruitment into 22 rivers, a statistical model is applied which relates the number of immigrating young eel caught in traps to the location and size of each river, the distance from the trap to the river mouth, and the year in which those eels recruited to continental waters as a glass eel (year class). The further into the Baltic, the larger and less numerous recruits generally are. Distance upstream comes with less numerous recruits. Using the results from the above recruitment analysis, in combination with historical data on assisted migration (young eels transported upstream within a drainage area, across barriers) and restocking (young eels imported into a river system), we have a complete overview of how many young eels recruited to Swedish inland waters. From this, the production of fully grown silver eel is estimated for every lake and year separately, based on best estimates of growth and natural mortality rates. Subtracting the catch made by the fishery (as recorded) and down-sizing for the mortality incurred when passing hydropower stations (percentwise, as recorded or using a default percentage), an estimate of the biomass of silver eel escaping from each river towards the sea is derived. Results indicate, that since 1960, the production of silver eel in inland waters has declined from over 700 to below 300 tonnes per year (t/yr). The production of naturally recruited eels is still falling; following the increase in restocking since 2010, an increase in restocking-based production is expected to be starting right around now. Gradually, restocking has replaced natural recruitment (assisted and fully natural), now making up over 90 % of the inland stock. Fisheries have taken 20-30 % of the silver eel (since the mid-1980s), while the impact of hydropower has ranged from 25 % to 60 %, depending on the year. Escapement is estimated to have varied from 72 t in the late 1990s, to 175 t in the early 2000s. The biomass of current escapement (including eels of restocked origin) is approximately 15 % of the pristine level (incl. restocked), or almost 30 % of the current potential biomass (incl. restocked). This is below the 40 % biomass limit of the Eel Regulation, and anthropogenic mortality (70 % over the entire life span in continental waters) exceeds the limit implied in the Eel Regulation (60 % mortality, the complement of 40 % survival). Mortality being that high, Swedish inland waters currently do not contribute to the recovery of the stock. The temporal variation (in production, impacts and escapement) is partly the consequence of a differential spatial distribution of the restocking of eel over the years. The original natural (not assisted) recruits were far less impacted by hydropower, since they could not climb the hydropower dams when immigrating. Since 2010, inland restocking is increasingly concentrated to drainage areas falling to the Kattegat-Skagerrak, also including obstructed lakes (primarily Lake Vänern, and many smaller ones). Even though Trap & Transport of silver eel - from above barriers towards the sea - has contributed to reducing the hydropower impact, hydropower mortality remains the largest estimated contributor to silver eel mortality in inland waters. Without restocking, the biomass affected by fishery and/or hydropower would be only 5-10 % of the currently impacted biomass, but the stock abundance would reduce from 15 % to less than 3 % of the pristine biomass. In summary: the inland eel stock biomass is below the minimum target, anthropogenic impacts exceed the minimum limit that would allow recovery, and those impacts have been increasing. It is therefore recommended to reconsider the current action plans on inland waters, taking into account the results of the current, comprehensive assessment. For the Baltic coast, the 2021 assessment has been updated without major changes in methodology. Results indicate that the impact of the fishery continues to decline over the decades. The current impact of the Swedish silver eel fishery on the escapement of silver eel along the Baltic Sea coast is estimated at 0.3 %. However, this fishery is just one of the anthropogenic impacts (in other areas/countries) affecting the eel stock in the Baltic, including all types of impacts, on all life stages and all habitats anywhere in the Baltic. Integration with the assessments in other countries has not been achieved. Current estimates of the abundance of silver eel (biomass) indicates an order of several thousand tonnes, but those estimates are extremely uncertain, due to the low impact of the fishery (near-zero statistics). Moreover, these do not take into account the origin of those silver eels, from other countries. An integrated assessment for the whole Baltic will be required to ground-truth these estimates. This would also bring the eel assessments in line with the policy to regionalise stock assessments for other (commercial) fish species (see https://ec.europa.eu/oceans-and-fisheries/fisheries/rules/multiannual-plans_en). It is recommended to develop an integrated assessment for the entire Baltic Sea eel stock, and to coordinate protective measures with other range states.
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