• Journal of the Korean Society for Library and Information Science
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• v.35 no.3
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• pp.173-189
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• 2001

This paper presents a framework for observable behavior that can be used as a basis for user modeling, and it reports the results of a pair of user studies that examine the joint utility of two specific behaviors. User models can be constructed by hand, or they can be teamed automatically based on feedback provided by the user about the relevance of documents that they have examined. By observing user behavior, it is possible to obtain implicit feedback without requiring explicit relevance judgments. Four broad categories of potentially observable behavior are identified : examine, retain, reference, and annotate, and examples of specific behaviors within a category are further subdivided based on the natural scope of information objects being manipulated . segment object, or class. Previous studies using Internet discussion groups (USENET news) have shown reading time to be a useful source of implicit feedback for predicting a user's preferences. The experiments reported in this paper extend that work to academic and professional journal articles and abstracts, and explore the relationship between printing behavior and reading time. Two user studies were conducted in which undergraduate students examined articles or abstracts from the telecommunications or pharmaceutical literature. The results showed that reading time can be used to predict the user's assessment of relevance, that the mean reading time for journal articles and technical abstracts is longer than has been reported for USENET news documents, and that printing events provide additional useful evidence about relevance beyond that which can be inferred from reading time. The paper concludes with a brief discussion of the implications of the reported results.

• Journal of the Korean Society of Systems Engineering
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• v.14 no.2
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• pp.24-32
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• 2018

System Complexity one of the most common cause failure of the projects, it leads to a lack of understanding about the functions of the system. Hence, the model is developed for communication and furthermore modeling help analysis, design, and understanding of the system. On the other hand, the text-based specification is useful and easy to develop but is difficult to visualize the physical composition, structure, and behaviour or data exchange of the system. Therefore, it is necessary to transform system description into a diagram which clearly depicts the behaviour of the system as well as the interaction between components. According to the International Atomic Energy Agency (IAEA) Safety Glossary, The safety system is a system important to safety, provided to ensure the safe shutdown of the reactor or the residual heat removal from the reactor core, or to limit the consequences of anticipated operational occurrences and design basis accidents. Core Protection Calculator System (CPCS) in Advanced Power Reactor 1400 (APR 1400) Nuclear Power Plant is a safety critical system. CPCS was developed using systems engineering method focusing on Departure from Nuclear Boiling Ratio (DNBR) calculation. Due to the complexity of the system, many diagrams are needed to minimize the risk of ambiguities and lack of understanding. Using Model-Based Systems Engineering (MBSE) software for modeling the DNBR algorithm were used. These diagrams then serve as the baseline of the reverse engineering process and speeding up the development process. In addition, the use of MBSE ensures that any additional information obtained from auxiliary sources can then be input into the system model, ensuring data consistency.

• Steel and Composite Structures
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• v.35 no.2
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• pp.279-294
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• 2020

Foundation of a building is damaged under service loads during construction. First visit shows that the foundation has been punched at the 6 column's foot region led to building rotation. Foundation shear punching occurring has made some stresses and deflections in construction. In this study, progressing of damage caused by foundation shear punching and inverse loading in order to resolve the building rotation has been evaluated in the foundation and frame of building by finite element modeling in ABAQUS software. The stress values of bars in punched regions of foundation has been deeply exceeded from steel yielding strength and experienced large displacement based on software's results. On the other hand, the values of created stresses in the frame are not too big to make serious damage. In the beams and columns of ground floor, some partial cracks has been occurred and in other floors, the values of stresses are in the elastic zone of materials. Finally, by inverse loading to the frame, the horizontal displacement of floors has been resolved and the values of stresses in frame has been significantly reduced.

• Journal of the Korean Geotechnical Society
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• v.27 no.8
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• pp.63-71
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• 2011

In case of applying BIM method to the civil engineering of irregularly shaped structure, BIM method is recognized to have relatively high construction productivity. In this paper, we developed quantity calculation algorithms applying BIM method to NATM tunnel construction method and implemented BIM based 3D-BIM Modeling Quantity Calculation. The results showed that BIM-based method has high reliabilty in structure work in which errors occurred only in the range between 0.00% and -1.45%. On the other hand, BIM method applied to earth work showed great error range of -19.78% to 35.30%. So the benefit and applicability of BIM method in civil engineering were confirmed. In addition, routine method for the quantity of earth work has negligible error as in the case of structure work. But, rock type's quantity calculation showed significant errors so that the reliability of 2D-based volume calculation is problematic. It may thus be concluded that 3D-BIM is more reliable than the routine method in estimating the quantity of earth work. Considering the reliability and merits in the stage of its design, construction and maintenance levels, the application of BIM to civil engineering works is recommended.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2355-2363
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• 2002

The accompanying paper, Part 1, has presented the physical modeling and basic numerical analysis results of both the flow-induced and thermally-induced residual stress and birefringence in injection molded center gated disks. The present paper, Part II, has attempted to investigate the effects of various processing conditions of injection/compression molding process on the residual stress and birefringence. The birefringence is significantly affected by injection melt temperature, packing pressure and packing time. Birefringence in the shell layer increases as melt temperature gets lower. The inner peak of birefringence increases with packing time and packing pressure. On the other hand, packing pressure, packing time and mold wall temperature affect the thermally-induced residual stress rather significantly in the shell layer, but insignificantly in the core region. Injection/compression molding has been found to reduce the birefringence in comparison with the conventional injection molding process. In particular, mold closing velocity and initial opening thickness in the compression stage of injection/compression molding process have significant effect on the flow-induced birefringence, but not on tile thermal residual stress and the thermally induced birefringence.

• Journal of Internet Computing and Services
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• v.19 no.5
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• pp.107-113
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• 2018

Object-oriented databases (OODBs) canbe used for many non-traditional database application areas such as computer-aided design, etc. Usually those application areas require advanced modeling power for expressing complicated relationships among data sets. OODBs have more distinguished features than the traditional relational database systems. One of the distinguished characteristics of OODBs is class hierarchy (also called inheritance hierarchy). A class hierarchy in an OODB means that a class can hand down the definitions of the class to the subclass of the class. In other words, a class is allowed to inherit the definitions of the class from the superclass. In this paper, we present performance evaluation metrics for class hierarchy in OODBs from a concurrency control perspective. The proposed performance metrics are developed to determine which concurrency control scheme in OODBs can be used for a given class hierarchy. In this study, in order to develop performance metrics, we use class hierarchy structure (both of single inheritance and multiple inheritance), and data access frequency for each class. The proposed performance metrics will be also used to compare performance evaluation for various concurrency control techniques.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.20 no.3
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• pp.243-259
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• 2016

The Richards equation for water movement in unsaturated soil is highly nonlinear partial differential equations which are not solvable analytically unless unrealistic and oversimplifying assumptions are made regarding the attributes, dynamics, and properties of the physical systems. Therefore, conventionally, numerical solutions are the only feasible procedures to model flow in partially saturated porous media. The standard Finite element numerical technique is usually coupled with an Euler time discretizations scheme. Except for the fully explicit forward method, any other Euler time-marching algorithm generates nonlinear algebraic equations which should be solved using iterative procedures such as Newton and Picard iterations. In this study, lumped mass and distributed mass in the frame of Picard and Newton iterative techniques were evaluated to determine the most efficient method to solve the Richards equation with finite element model. The accuracy and computational efficiency of the scheme and of the Picard and Newton models are assessed for three test problems simulating one-dimensional flow processes in unsaturated porous media. Results demonstrated that, the conventional mass distributed finite element method suffers from numerical oscillations at the wetting front, especially for very dry initial conditions. Even though small mesh sizes are applied for all the test problems, it is shown that the traditional mass-distributed scheme can still generate an incorrect response due to the highly nonlinear properties of water flow in unsaturated soil and cause numerical oscillation. On the other hand, non oscillatory solutions are obtained and non-physics solutions for these problems are evaded by using the mass-lumped finite element method.

• Journal of Information Processing Systems
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• v.10 no.3
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• pp.365-383
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• 2014

Service-oriented computing offers efficient solutions for executing complex applications in an acceptable amount of time. These solutions provide important computing and storage resources, but they are too difficult for individual users to handle. In fact, Service-oriented architectures are usually sophisticated in terms of design, specifications, and deployment. On the other hand, workflow management systems provide frameworks that help users to manage cooperative and interdependent processes in a convivial manner. In this paper, we propose a workflow-based approach to fully take advantage of new service-oriented architectures that take the users' skills and the internal complexity of their applications into account. To get to this point, we defined a novel framework named JASMIN, which is responsible for managing service-oriented workflows on distributed systems. JASMIN has two main components: unified modeling language (UML) to specify workflow models and business process execution language (BPEL) to generate and compose Web services. In order to cover both workflow and service concepts, we describe in this paper a refinement of UML activity diagrams and present a set of rules for mapping UML activity diagrams into BPEL specifications.

• Journal of Magnetics
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• v.22 no.2
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• pp.326-332
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• 2017

The effects of exposure to an extremely low-frequency magnetic field (25 Hz 20G) on animal cells have been studied. In some reports, stimulation was performed for fixed frequency and variations in magnitude; however, animal-cell experiments have established that both parameters play an important role. The present work undertook the modeling, simulation, and development of a uniform-magnetic-field generation system with variable frequency and stimulation intensity (0-60 Hz, 1-25G) for experimentation with cell cultures in situ. The results showed a coefficient of variation less than 1 % of the magnetic-field dispersion at the working volume, which is consistent with the corresponding simulation results demonstrating a uniform magnetic field. On the other hand, long-term tests during the characterization process indicated that increments of only $0.4^{\circ}C$ in the working volume temperature will not be an interfering factor when experiments are carried out in in situ cell cultures.

• Geomechanics and Engineering
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• v.24 no.3
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• pp.281-293
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• 2021

Uncertainties in geomechanical input parameters which mainly related to inappropriate data acquisition and estimation due to lack of sufficient calibration information, have led wellbore instability not yet to be fully understood or addressed. This paper demonstrates a workflow of employing Quantitative Risk Assessment technique, considering these uncertainties in terms of rock properties, pore pressure and in-situ stresses to makes it possible to survey not just the likelihood of accomplishing a desired level of wellbore stability at a specific mud pressure, but also the influence of the uncertainty in each input parameter on the wellbore stability. This probabilistic methodology in conjunction with Monte Carlo numerical modeling techniques was applied to a case study of a well. The response surfaces analysis provides a measure of the effects of uncertainties in each input parameter on the predicted mud pressure from three widely used failure criteria, thereby provides a key measurement for data acquisition in the future wells to reduce the uncertainty. The results pointed out that the mud pressure is tremendously sensitive to UCS and SHmax which emphasize the significance of reliable determinations of these two parameters for safe drilling. On the other hand, the predicted safe mud window from Mogi-Coulomb is the widest while the Hoek-Brown is the narrowest and comparing the anticipated collapse failures from the failure criteria and breakouts observations from caliper data, indicates that Hoek-Brown overestimate the minimum mud weight to avoid breakouts while Mogi-Coulomb criterion give better forecast according to real observations.