Bao Hua Huang, Tian Jing Wang, Yan Ma et al. · Applied Mechanics and Materials · 2014
Sensitive data in database should be encrypted to protect it from malicious access. Do this in application is hard and costly. Utilizing the user-defined function technology supported by database management system, data encryption could be done separately and transparently for application. The principle and system architecture of encrypting database content with user-defined function is introduced, and the method handling long object encrypting is discussed specially. Experiments show that the proposed method is easy to implement, effective in system running and application development, and applicable for both new developing and old developed application.
Cited by 1Open access
Varun Simhadri, Karthik Ramachandra, Arun Chaitanya et al. · 2014
Queries containing user-defined functions (UDFs) are widely used, since they allow queries to be written using a mix of imperative language constructs and SQL, thereby increasing the expressive power of SQL; further, they encourage modularity, and make queries easier to understand. However, not much attention has been paid to their optimization, except for simple UDFs without imperative constructs. Queries invoking UDFs with imperative constructs are executed using iterative invocation of the UDFs, leading to poor performance, especially if the UDF contains queries. Such poor execution has been a major deterrent to the wider usage of complex UDFs. In this paper we present a novel technique to decorrelate UDFs containing imperative constructs, allowing set-oriented execution of queries that invoke UDFs. Our technique allows imperative execution to be modeled using the Apply construct used earlier to model correlated subqueries, and enables transformation rules to be applied subsequently to decorrelate (or inline) UDF bodies. Subquery decorrelation was critical to the wide use of subqueries; our work brings the same benefits to queries that invoke complex UDFs. We have applied our techniques to UDFs running on two commercial database systems, and present results showing up to orders of magnitude improvement.
Cited by 23
Matthew Stickland, Sylvie Fabre, Thomas Scanlon · Strathprints: The University of Strathclyde institutional repository (University of Strathclyde) · 2011
This report describes the Fluent User Defined Function WindCube_comp_sim used to interrogate FLUENT a Fluent data set by simulating the operation of a LeoSphere Windcube LiDAR. The user defined function is contained in the program lidar.c (version 1.06) which has been written in the C programming language. This report contains a listing of the user defined function, describes its method of operation and presents a validation of the analysis process. The report also includes a description of the output data file formats.
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Ganić, Aleksandar, Milutinović, Aleksandar, Ganić, Meri · SCIndeks · 2014
The topographic plane of the Earth has irregular shape, and for the purpose of mathematical defining, it is to be approximated by rotational ellipsoid. As local geodetic datum, rotational ellipsoids of various sizes are used in the world. More widely usage of the GPS while performing surveying tasks has resulted in the need to define global geodetic datum in order to obtain the best approximation the entire Earth. For this purpose, geocentric rotational ellipsoid WGS84 was defined and the results of the GPS measurements are shown in relation to it. By applying the appropriate equations, the ellipsoidal coordinates are being transformed from WGS84 into the coordinates on the local rotational ellipsoid, i.e. on the view plane. The paper shows User Defined Function created for Excel, by which the coordinates in the territory of Belgrade are being transformed from WGS84 of rotational ellipsoid into the Gauss-Krüger projection plane.
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Sawaki, Yasunori · Zenodo (CERN European Organization for Nuclear Research) · 2023
Features User-defined read function available Update <code>OrientSingle</code> & <code>OrientAnalysis</code> New function read_result() that reads the output file in csv, json, or pickle. Changes In <code>OrientOBS</code>, <code>fileformat</code> was renamed as <code>filenameformat</code> in v0.3.0. <code>fileformat</code> denotes the data format of the records. Remove the call of stats.sac See #1
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Rafael G. González-Acuña · Journal of the Optical Society of America A · 2021
Here we present a method to design a stigmatic lens with a user-defined apodization pupil function. The motive is that the apodization pupil function is required by Richards-Wolf diffraction integrals to compute non-paraxial diffraction patterns. Then, the user-defined apodization pupil function can be chosen such that the focus spot obtained by the stigmatic lens is smaller. The mentioned method is based on numerically solving a non-linear differential equation.
Cited by 5
Adriana Gaia Cairelli (12800504), Renee Wei-Yan Chow (11949860), Julien Vermot (257990) et al. · Figshare · 2022
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Rodrigo Palucci Pantoni, Eduardo André Mossin, Victor Teixeira C. Halfeld et al. · Journal of Electrical Systems and Information Technology · 2024
Abstract In recent decades, standardisation has become crucial in Industrial Automation Systems, promoting interoperability among devices from different manufacturers. Nonetheless, the portability of manufacturing engineering tools continues to present a significant challenge. AutomationML (IEC 62714 -5) has played a role in formulating strategies that leverage O-PAS Standard Function Blocks. The O-PAS specification includes several standards, such as IEC 62443, IEC 61499, IEC 61131–3, OPC-UA (Open platform communications unified architecture), DCS (Distributed control system), and PLC (Programmable logic controller). This highlights the necessity of integrating new technologies with legacy systems to achieve enhanced interoperability. In this context, this work proposes the development of User-Defined Function Blocks (UDFB) that adhere to O-PAS standards and can be implemented across any compliant system. The proposed methodology is aligned with O-PAS standards, leading to the inclusion of UDFB information in XML format within the Function Block Library and AutomationML.
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Jacob, Jeslu Celine · Figshare · 2024
User-defined function written in C to be compiled in ANSYS fluent for evaluating age of air
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Qiyu Liu, Libin Zheng, Xiang Lian et al. · Lecture notes in computer science · 2021
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Jacob, Jeslu Celine · Figshare · 2024
User-defined function written in C to be compiled in ANSYS fluent for evaluating age of air
Cited by 1Open access
Jun Jie Tan · DR-NTU (Nanyang Technological University) · 2017
In a typical building, half of the total energy consumption are consumed by the Heating, Ventilating and Air-Conditioning (HVAC) systems. HVAC systems provide heating, cooling and remove contaminated air to maintain the occupants’ thermal comfort and the indoor air quality (IAQ). The use of energy is efficiently utilized through well-designed HVAC systems. With the use of Computational Fluid Dynamics (CFD), the expected flow in rooms and buildings is simulated. \nThe purpose of this project is to obtain an optimal airflow pattern with an occupant in the room using User-Defined Function (UDF). This study utilizes the software, ANSYS/FLUENT to simulate the ventilation in a 2-Dimensional (2D) room and analyzes the airflow patterns. An occupant is added in the room at three locations to investigate on the difference in the airflow pattern. Comparison of the airflow patterns between different configurations are displayed. Reversible and Irreversible UDF are applied and various effects are shown in each of the cases. \nThe results are collected and discussions are made to determine the better configuration between the cases as well as the suitable type of UDF to be used in the cases. It is found that Irreversible UDF yields better thermal comfort when the inlet and outlet are on the same wall or when the outlet is near to the inlet. Reversible UDF is more suitable for rooms where the outlet is on the opposite wall or further from the inlet. When the occupant is located near the inlet, Reversible UDF works better for both cases. The findings in this project are valuable for real-life applications.
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Jiali Wang (593779), Peifan Li (6084596), Xiaozhen Yu (587658) et al. · Figshare · 2021
<p>(A) Substrate-protein successive binding steps. In simulations with user-defined force, within a short period of simulation time, aspartate will move close to HP2 loop, but the binding pocket is not accessible when the HP2 loop is not fully open. Once the open-gate state forms (HP2-HP1 distance larger than 12 Å), aspartate is able to move inside the binding pocket. At this moment, the conserved residues located in TM7 stabilize the aspartate. (B-D) Coordination states with open loop from user-defined force simulation results are shown in pink. Comparison of the crystal structure (2nwx) is shown in grey. All simulation results were from sampling by adding user-defined force to conventional MD simulations. Two distinguishable binding positions are shown in (D) and (E), (F). One overlaps with the binding site in the crystal structure (D) and another (E, F) is located at a higher Z-axis position. (E) Aspartate bound in HP2 half-open state, and (F, G) in HP2 fully-open state. (H-K) Time evolution of distance calculation (black) and HP2-HP1 distance (red) shown in each picture, respectively. The blue line indicates the user-defined force boundary and the grey bar region indicates the time of force application. In the region below the blue line (distance<7Å) or not covered by the grey bar, no user-defined forces were added to substrate, and conventional MD were sampled here. The right panels of each graph show aspartate radial distribution functions (black) and cumulative radial distribution functions (blue). Results were analyzed within 10 Å distance from the reference Arg-397 residue (atom CG).</p>
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Zeqian Wang, Hao Wang, Ye Su et al. · IEEE Transactions on Services Computing · 2026
Skyline query is a fundamental technique in multi-criteria decision-making, aiming to extract “optimal” results that are not dominated by any other data points across all attributes. It has significant value in applications that require trade-offs among multiple criteria. However, existing skyline query methods face two critical limitations: (i) conventional approaches adopt fixed dominance relationships, making it difficult to capture personalized user preferences; and (ii) cloud-based deployment models risk exposing sensitive data and query logic, making it difficult to ensure data privacy and protect query patterns while maintaining efficiency. To address these issues, we propose Privacy-Preserving User-Defined Skyline Query (PUDSQ), a novel privacy-preserving user-defined skyline query framework, which integrates efficient cryptographic techniques–secret sharing (SS) and function secret sharing (FSS)–with a secure database shuffling mechanism to achieve efficient query processing while ensuring robust privacy guarantees. PUDSQ introduces three main innovations: (i) a privacy-preserving filtering framework based on FSS provides dual protection for both data content and user preferences, effectively concealing database content and query logic; (ii) an FSS-based secure protocol suite supporting user-defined attribute retrieval, constrained-region retrieval, and secure skyline filtering; and (iii) a high-dimensional data processing strategy that integrates dimensionality reduction with an Sort-Filter-Skyline (SFS)-based presorting approach to address the high-dimensional data processing challenge and significantly improve efficiency. Experimental results demonstrate that, under equivalent security guarantees, PUDSQ reduces query latency by 8%-90% compared with state-of-the-art solution, with particularly notable advantages in high-dimensional scenarios, achieving an effective efficiency-privacy trade-off.
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Ong, Aidan Jiong Shun · DR-NTU (Nanyang Technological University) · 2017
Singapore is known for having a tropical climate with hot and humid weather all year \nround. The abundance of high-rise buildings on this tiny red dot have led to wind \nobstructions and resulted in an undefined distribution of air flow. This effect affects \nurban resident’s summer discomfort and greatly increases air conditioning loads. \nWith this rising concern, the national authorities have incorporated the “Heating, \nVentilating and Air-Conditioning” (HVAC) system into residential structures to \nimprove thermal comfort. However, this implementation can potentially lead to \nhigher energy consumption and worsens global warming. \nThrough the advancement of modern technology, Computational Fluid Dynamics \n(CFD) is used extensively today by researchers to investigate and analyse the \nexpectancy of air flow flowing into the indoor buildings. \nThe methodology of the numerical experiment is applied on ANSYS/Fluent software. \nFirstly, a geometric model is drawn based on two cases of two-dimensional \nconfiguration profiles, with and without heat source respectively. Next, the meshing \nconsiderations allow for refinement and enhancement on the mesh size, and the \n‘Named selection’ feature function to state the design components. Subsequently, the \nboundary conditions for the input parameters such as the direction of air flow, range \nof time, air temperature and position of inlet and outlet differs for the respective two \ncases. Lastly, the setup in key parameters further improvises the iteration results, \nwhereby timing is crucial for the generation of the contour and vector plots. \nUser-Defined Function (UDF) is a written programme source code that controls the \nair flow velocity direction with respect to time and with the velocity magnitude \nremains constant. With the iterated results, the air flow velocity and the temperature \nof contour and vector plots are compared and discussed with no UDF, irreversible \nUDF and reversible UDF respectively. For further validation, the heat sources are \nidentified as real life occupants are added in the numerical experiment to give more \nlogical and realistic results. Therefore, the objective of this project study is to show \nthrough the two-dimensional configuration profiles room, that UDF is able to help \nachieve optimal air flow and thermal distribution.
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Othonas Manis, Michalis Skoumperdis, Christos Kioroglou et al. · Sensors · 2024
This paper explores the energy-intensive cement industry, focusing on a plant in Greece and its mill and kiln unit. The data utilized include manipulated, non-manipulated, and uncontrolled variables. The non-manipulated variables are computed based on the machine learning (ML) models and selected by the minimum value of the normalized root mean square error (<i>NRMSE</i>) across nine (9) methods. In case the distribution of the data displayed in the user interface changes, the user should trigger the retrain of the AI models to ensure their accuracy and robustness. To form the objective function, the expert user should define the desired weight for each manipulated or non-manipulated variable through the user interface (UI), along with its corresponding constraints or target value. The user selects the variables involved in the objective function based on the optimization strategy, and the evaluation is based on the comparison of the optimized and the active value of the objective function. The differential evolution (DE) method optimizes the objective function that is formed by the linear combination of the selected variables. The results indicate that using DE improves the operation of both the cement mill and kiln, yielding a lower objective function value compared to the current values.
Cited by 2Open access
Othonas Manis, Michalis Skoumperdis, Christos Kioroglou et al. · Preprints.org · 2023
The energy-intensive sector of the cement industry needs to find technologically advanced methods to produce cement with as little energy as possible, without polluting the environment and without sacrificing the quality (fineness) of the cement. In addition, the stress on the machines changes the behavior of the data. By combining the k-means method, two (2) feature selection methods, nine (9) machine learning methods, and the differential evolution (DE) method, a dynamic system is created where the user determines the key performance indicators (KPIs) each time. The user has the potential to control the distribution of the data, the input of machine learning models, and the ability to switch the system to the suggested values without damage. The selection of the best-performing models is based on the normalized root mean squared error (NRMSE). The DE method optimizes the dynamic objective function. The optimal values of the manipulated variables are evaluated compared to the value of the objective function from the actual values of the variables. In all experiments, the recommendations are acceptable. The final results show an improvement in the operation of both the cement mill and kiln compared to the current operating condition.
Cited by 2Open access
Flores-Hidalgo, Manuel Alberto · BiblioBoard Library Catalog (Open Research Library) · 2022
Heat effects in photocatalytic reactor applications are discussed and a case study is analyzed where sunlight is used to activate a chemical reaction to degrade water pollutants. Heat is produced in the light-capturing process, and heat effects need to be better understood during the device design process. Radiative transfer equation (RTE) is the guiding equation used to calculate radiation proliferation in participating media, and it is used to describe the balance of radiative energy transport in the participating media including the interactions caused by different processes such as absorption, scattering, and emission, which also are subject to additional phenomena like weakening and magnification. This equation plays an important role in the design process since it may be included in the simulation process to represent the sunlight heat effects in the different photocatalytic reactor components. In this chapter, it is explained how to build a simplified algorithm to incorporate the RTE in a numerical calculation during the design of a photocatalytic reactor using the commercial software ANSYS®. In addition, simplifications are explained that enable the program to coordinate some coefficients such as absorption and dispersion so their effects are included within the numerical calculation. A user-defined function is presented in the end of the chapter as a usable algorithm in ANSYS® program with acceptable results for photocatalytic reactors.
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F.X. Yu, Vijay P. Singh · Advances in Engineering Software · 1993
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Susan Kealey, Vilert A. Loving, David M. DeLong et al. · Radiology · 2004
The authors reviewed 40 computed tomographic (CT) perfusion studies to determine the effect of arterial and venous input function properties on perfusion parameter values and tissue signal-to-noise ratio (SNR). A 10-subject subset was analyzed to evaluate the effect of varying venous region of interest (ROI) locations. Venous peak enhancement correlated significantly with mean tissue cerebral blood flow (CBF) and cerebral blood volume (CBV); venous and arterial peak enhancement correlated significantly with SNR of perfusion maps. Different ROI locations within the same vein resulted in significantly different CBV and CBF values. Perfusion map parameters are related to peak enhancement within user-selected ROIs. Optimal ROI selection should limit variability and increase quality of CT perfusion images.
Cited by 56