• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.7
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• pp.1-10
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• 2002

Multidisciplinary Design Optimization (MDO) is a new design approach, which aims to reduce the design cycle and the development cost, while improving the performance of the product. In order to develop a framework software where the multidisciplinary design is possible, several methods about the analysis codes integration, the analysis and optimization process management, and the software architecture, are proposed in this study. Centralized DataBase Management System (DBMS) is adopted. Both the Dynamic Link Library(DLL) and the File Interface are suggested and implemented as analysis codes integration methods. To efficiently manage the optimization process and the data flow, the Graphic Programming approach is introduced. The proposed integration methods are verified by two test case examples: Simple house design example and the aircraft wing design problem using three dimensional Panel Code.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1234-1249
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• 2017

One of the difficulties developers encounter in maintaining tasks of a large-scale software system is the updating of suitable libraries on time. Developers tend to miss or make mistakes when searching for and choosing libraries during the development process, or there may not be a stable library for the developers to use. We present a novel approach for helping developers modify software easily and on time and avoid software failures. Using a tool previously built by us called GPES, we collected information of projects, such as abstract syntax trees, tokens, software metrics, relations, and evolutions, for our experiments. We analyzed the contexts of source codes in existing projects to predict changes automatically and to recommend suitable libraries for the projects. The collected data show that researchers can reduce the overall cost of data analysis by transforming the extracted data into the required input formats with a simple query-based implementation. Also, we manually evaluated how the extracted contexts are similar to the description and we found that a sufficient number of the words in the contexts is similar and it might help developers grasp the domain of the source codes easily.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.6
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• pp.1225-1236
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• 2020

Fuzzing is an automated software testing methodology that dynamically tests the security of software by inputting randomly generated input values outside of the expected range. KISA is releasing open source for standard cryptographic algorithms, and many crypto module developers are developing crypto modules using this source code. If there is a vulnerability in the open source code, the cryptographic library referring to it has a potential vulnerability, which may lead to a security accident that causes enormous losses in the future. Therefore, in this study, an appropriate security policy was established to verify the safety of block cipher source codes such as SEED, HIGHT, and ARIA, and the safety was verified using differential fuzzing. Finally, a total of 45 vulnerabilities were found in the memory bug items and error handling items, and a vulnerability improvement plan to solve them is proposed.

• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2725-2732
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• 2020

This paper presents the neutronics benchmark analysis of the first core of the Indonesian multipurpose research reactor RSG-GAS (Reaktor Serba Guna G.A. Siwabessy) calculated by the Serpent Monte Carlo code and the newly released ENDF/B-VIII.0 nuclear data library. RSG-GAS is a 30 MWth pool-type material testing research reactor loaded with plate-type low-enriched uranium fuel using light water as a coolant and moderator and beryllium as a reflector. Two groups of critical benchmark problems are derived on the basis of the criticality and control rod calibration experiments of the first core of RSG-GAS. The calculated results, such as the neutron effective multiplication factor (k) value and the control rod worth are compared with the experimental data. Moreover, additional calculated results, including the neutron spectra in the core, fission rate distribution, burnup calculation, sensitivity coefficients, and kinetics parameters of the first core will be compared with the previous nuclear data libraries (interlibrary comparison) such as ENDF/B-VII.1 and JENDL-4.0. The C/E values of ENDF/B-VIII.0 tend to be slightly higher compared with other nuclear data libraries. Furthermore, the neutron reaction cross-sections of ¹⁶O, ⁹Be, ²³⁵U, ²³⁸U, and S(𝛼,𝛽) of ¹H in H₂O from ENDF/B-VIII.0 have substantial updates; hence, the k sensitivities against these cross-section changes are relatively higher than other isotopes in RSG-GAS. Other important neutronics parameters such as kinetics parameters, control rod worth, and fission rate distribution are similar and consistent among the nuclear data libraries.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.6
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• pp.1385-1397
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• 2015

The Proxy DLL is a mechanism using a normal characteristics of Windows. Specific malware is executed via this mechanism after intrusion into a system which is targeted. If a intrusion of malware is successful, malware should be executed at least once. For execution, malware is disguised as a Windows Library. The malware of Winnti group is a good case for this. Winnti is a group of Chinese hacking groups identified by research in the fall of 2011 at Kaspersky Lab. Winnti group activities was negatively over the years to target the online video game industry, in this process by making a number of malware infected the online gaming company. In this paper, we perform research on detection techniques of Proxy DLL malware which is disguised as a Windows library through Winnti group case. The experiments that are undertaken to target real malware of Winnti show reliability of detection techniques.

• ETRI Journal
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• v.25 no.5
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• pp.337-344
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• 2003

In this paper, we introduce a fully synthesizable 32-bit embedded microprocessor core called the AE32000B. The AE32000B core is based on the extendable instruction set computer architecture, so it has high code density and a low memory access rate. In order to improve the performance of the core, we developed and adopted various design options, including the load extension register instruction (LERI) folding unit, a high performance multiply and accumulate (MAC) unit, various DSP units, and an efficient coprocessor interface. The instructions per cycle count of the Dhrystone 2.1 benchmark for the designed core is about 0.86. We verified the synthesizability and the area and time performances of our design using two CMOS standard cell libraries: a 0.35-${\mu}m$ library and a 0.18-${\mu}m$ library. With the 0.35-${\mu}m$ library, the core can be synthesized with about 47,000 gates and operate at 70 MHz or higher, while it can be synthesized with about 53,000 gates and operate at 120 MHz or higher with the 0.18-${\mu}m$ library.

• Journal of the Korean Society for information Management
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• v.14 no.2
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• pp.105-122
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• 1997

A library for the civil engineering field goes on increasing in quantity because of the growth in construction technology and the enlargement in applicable fields of civil engineering. Most of libraries and information centers in construction companies are using Dewey Decimal Classification (DDC) or Korean Decimal Classification (KDC) to classify a library in civil engineering field. It is necessary for the library classification system to be equipped with a more standardized code system, which corresponds to the academical and technical classification for the civil engineering works. This study analyzes the defects of existing classification systems, and then suggests a new classes and divisions classification system, which facilitates to link academic information with technical data, for the civil engineering field. The proposed system is expected to make practical application of information classification system in the construc ion industry and to be applied for the revised edition of KDC.

• Journal of the Korea Society of Computer and Information
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• v.26 no.2
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• pp.1-9
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• 2021

In this paper, we extend a generic library framework based on the state monad to exploit deterministic parallelism in a purely functional language Haskell and provide benchmarks for the extended features on a multicore machine. Although purely functional programs are known to be well-suited to exploit parallelism, unintended squential data dependencies could prohibit effective parallelism. Symbolic execution programs usually implement fresh name generation in order to prevent confusion between variables in different scope with the same name. Such implementations are often based on squential state management, working against parallelism. We provide reusable primitives to help developing parallel symbolic execution programs with unbound-genercis, a generic name-binding library for Haskell, avoiding sequential dependencies in fresh name generation. Our parallel extension does not modify the internal implementation of the unbound-generics library, having zero possibility of degrading existing serial implementations of symbolic execution based on unbound-genecrics. Therefore, our extension can be applied only to the parts of source code that need parallel speedup.

• Journal of Korean Library and Information Science Society
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• v.54 no.3
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• pp.33-55
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• 2023

There has been research to understand users' information behaviors using book circulation data of public libraries. In this study, we examined the subject areas of books simultaneously borrowed by users of public libraries and aimed to identify the relationships among the subject areas. To accomplish this, we utilized the Korean Decimal Classification codes of 984,790 loaned books in 2019 to transform the lists of concurrently borrowed books, totaling 22,443,699 records, by the same users on the same day, into vectors using the ITEM2VEC technique. Next, we extracted ten highly related classification codes for each classification code, utilizing a total of 522 classification codes to create a network. We identified 15 communities within this network and examined the characteristics of each community. Among the 15 communities, those consisting of two or more main classes allowed us to identify meaningful thematic associations. This study, grounded in users' book usage behaviors, has suggested the topics of books that could be borrowed together. The findings offer valuable insights for library collection development and placement, recommending related subject materials, and revising classification systems.

• Nuclear Engineering and Technology
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• v.41 no.6
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• pp.785-796
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• 2009

A KALIMER-600 concept which is a type of sodium-cooled fast reactor, has been developed at KAERI. It uses sodium as a primary coolant and is a pool-type reactor to enhance safety. Also, a supercritical carbon dioxide ($CO_2$) Brayton cycle is considered as an alternative to an energy conversion system to eliminate the sodium water reaction and to improve efficiency. In this study, a simplified model for analyzing the thermodynamic performance of the KALIMER-600 coupled with a supercritical $CO_2$ Brayton cycle was developed. To develop the analysis model, a commercial modular modeling system (MMS) was adopted as a base engine, which was developed by nHance Technology in USA. It has a convenient graphical user interface and many component modules to model the plant. A new user library for thermodynamic properties of sodium and supercritical $CO_2$ was developed and attached to the MMS. In addition, some component modules in the MMS were modified to be appropriate for analysis of the KALIMER-600 coupled with the supercritical $CO_2$ cycle. Then, a simplified performance analysis code was developed by modeling the KALIMER-600 plant with the modified MMS. After evaluating the developed code with each component data and a steady state of the plant, a simple power reduction and recovery event was evaluated. The results showed an achievable capability for a performance analysis code. The developed code will be used to develop the operational strategy and some control logics for the operation of the KALIMER-600 with a supercritical $CO_2$ Brayton cycle after further studies of analyzing various operational events.