• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.9
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• pp.2074-2079
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• 1997

Much recent work has been done in the two related areas of source coding for data compression, and channel coding for data storage, respectively. We propose two (0, k) run-lengh limited(RLL) data compression codes for the storage that combine source and channel coding. It was shown that the propsoed codes approach the maximum code rate of (0, k) code as k increase. Thus, the overall code rate of storage system can be increased by using the combined source/channel coding as compared to the conventional 8/9 code which is popular in hard drive systems Functhermore, one can also reduce the complexity of modulation coding procedure by using already RLL constrained data.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.7
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• pp.1-8
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• 2008

Low Density Parity Check codes(LDPC) are recently focused on communication systems due to its good performance. The standard of WiBro has also included LDPC codes as a channel coding. The weak point of implementation for LDPC encoder is that conventional binary Matrix Vector Multiplier has many clock cycles which limit throughput. In this paper, we propose semi-parallel architecture by using cyclic shift registers and exclusive-OR without conventional Matrix Vector Multipliers over the standard parity check matrices with Circulant Permutation Matrices(CPM). Furthermore, multi-rate encoder is designed by using proposed architecture. Our encoder with multi-rate for IEEE 802.16e LDPC has lower clock cycles and higher throughput.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.1
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• pp.155-162
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• 1999

In this paper, an R_ALOHA_CDMA protocol is proposed for voice and data integrated services in the hybrid TDMA/CDMA wireless networks. In the hybrid TDMA/CDMA systems, the backward logical channels are composed of time slots with multiple spreading codes per slot. In the proposed protocol, a voice terminal can reserve a spreading code to transmit voice packets during a talkspurt. On the other hand, whenever a data terminal generates a packet, it transmits the packet through one of the available spreading codes. Throughout the results, it is shown that the system capacity increases in proportion to the number of spreading codes.

• The Korean Journal of Archival Studies
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• no.5
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• pp.209-242
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• 2002

Bibliographical Description for Revolutionary Historical Archives is created to describe records at the item level. It defines descriptive elements, punctuations, formats and methods. Descriptive elements are composed of 20 elements, each of which is either mandatory or optional. Mandatory elements are: repositories codes, documents codes, dates, creators, title, classification codes, and subject vocabularies. Abstracts were previously included in card cataloging and are removed in the computerized system. New elements, such as "uncontrolled vocabularies," "name of places," "personal names," "organizational structures" and "meetings," are added to allow keyword search. Considering that subject vocabulary searches are the most important in computerized systems, however, Guidelines for the Subject Indexing for Revolutionary Historical Archives as well as Subject Headings, as a result from the Guidelines, are created. The most extraordinary features in Chinese archival description are said to be the Guidelines for the Classification Indexing for Revolutionary Historical Archives and Materials as well as the Classification Scheme, both of which are created to allow subject search of records content. It is because Chinese practice of records management distinguishes the classification for arrangement from that for retrieval. Chinese archival description is, therefore, composed of bibliographic description rules, subject headings, and the classification scheme for retrieval.

• Journal of Information Science Theory and Practice
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• v.11 no.3
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• pp.43-57
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• 2023

Government codes are created and utilized to streamline and standardize government administrative procedures. They are generally employed in government information systems. Because they are included in open datasets of public data, users must be able to understand them. However, information that can be used to comprehend administrative code is lost during the process of releasing data in the government system, making it difficult for data consumers to grasp the code and limiting the connection or convergence of different datasets that use the same code.This study proposes a way to employ the administrative code produced by the Korean government as a standard in a public data environment on a regular basis. Because consumers of public data are barred from accessing government systems, a means of universal access to administrative code is required. An ontology model is used to represent the administrative code's data structure and meaning, and the full administrative code is built as a knowledge graph. The knowledge graph thus created is used to assess the accuracy and connection of administrative codes in public data. The method proposed in this study has the potential to increase the quality of coded information in public data as well as data connectivity.

• Structural Engineering and Mechanics
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• v.87 no.4
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• pp.347-361
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• 2023

This research aims to assess the behavior of reinforced concrete (RC) residential buildings when moment-resisting frames (MRFs) are used as the lateral resisting system. This investigation was conducted using MIDAS Gen v.19.0. Buildings with various plan footprints (Square, Rectangular, Circular, Triangular, and Plus-Shaped), and different heights (15 m, 30 m, 45 m, and 60 m) are investigated. The defined load cases, the equivalent static lateral load pattern, and the response spectrum function were defined as stated by the American Standard (ASCE 7-16), the 1997 Uniform Building Code (UBC97), the Egyptian Code for Loads (ECP-201), and the European Standard (EC8). Extensive comparisons of the results obtained by the different codes (including the story displacement, the story drift, and the base shear) were undertaken; to assess the response of moment-resisting multi-story framed buildings under lateral loads. The results revealed that, for all study cases under consideration, both ECP-201 and EC8 gave smaller base shear, displacement, and drift by one third to one fourth, around one fourth, around one fifth, respectively for both the ELF and RSA methods if compared to ASCE 7-16 and UBC97.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.79-80
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• 2023

Reinforced concrete structures require large amounts of concrete and rebar in the construction stage. Rebar is a major resource for reinforced concrete structures, and generates more CO₂ per unit weight than other materials. To solve this problem, it was confirmed that the cutting waste can be close to zero when the special length of the rebar is calculated in the drawing created after structural design. However, a system for automatically calculating the length of reinforcing bars to efficiently calculate the total amount of reinforcing bars has not been established. Therefore, the objective of this study is a basic study of automatic rebar length estimate algorithm of bearing wall by using BIM-based shape codes built in Revit. The bearing wall rebar can be automatically derived using the developed model. Furthermore, through applying the developed model to the construction field, it will greatly contribute to reducing greenhouse gas emissions by reducing rebar cutting waste.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.95-96
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• 2023

The purpose of this study is to derive the limitations of the existing management system by analyzing the characteristics of the PC process to improve the PC construction project management system process. To overcome the limitations derived, we present a process of managing integrated information from the design-production-construction stage using QR codes and clouds. This is expected to help develop a PC construction project management system.

• Korean Journal of Computational Design and Engineering
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• v.21 no.1
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• pp.31-41
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• 2016

Building Information Modeling (BIM) has been adopted in variety domain of construction industry. In this circumstances, interest of BIM model quality has been increased. In many countries, automated building code checking system by Industry Foundation Classes (IFC) has been developed and studied to use web based building permission systems. IFC is international standard of BIM format. However, the data structure of IFC does not include all of objects and properties about national building codes. In this paper, we developed the information specification between IFC data structure and national building code to increase interoperability. First, we drew the criteria from literature review to analyze the building code. And then, we analyzed building code and sorted objects and properties for automated building code checking. After that we made mapping table between the sorted data and IFC specification. Using the mapping table, we developed pre-specification about building codes information that does not exist in IFC specification. And the defined information can be used to develop the BIM modeling guide and national building permission system. The pre-specification support increasing the interoperability between user and automated building code checking system. Increasing thee interoperability makes improvement accuracy and reliability about result of automated building code checking.

• ETRI Journal
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• v.30 no.6
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• pp.807-817
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• 2008

We present a low-density parity-check (LDPC)-based, threaded layered space-time-frequency system with emphasis on the iterative receiver design. First, the unbiased minimum mean-squared-error iterative-tree-search (U-MMSE-ITS) detector, which is known to be one of the most efficient multi-input multi-output (MIMO) detectors available, is improved by augmentation of the partial-length paths and by the addition of one-bit complement sequences. Compared with the U-MMSE-ITS detector, the improved detector provides better detection performance with lower complexity. Furthermore, the improved detector is robust to arbitrary MIMO channels and to any antenna configurations. Second, based on the structure of the iterative receiver, we present a low-complexity belief-propagation (BP) decoding algorithm for LDPC-codes. This BP decoder not only has low computing complexity but also converges very fast (5 iterations is sufficient). With the efficient receiver employing the improved detector and the low-complexity BP decoder, the proposed system is a promising solution to high-data-rate transmission over selective-fading channels.