• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.19-33
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• 2024

In nuclear thermal-hydraulic system codes, most correlations used for vertical pipes, under downward two-phase flow, have been developed considering small pipes or pool systems. This suggests that there could be uncertainties in applying the correlations to accident scenarios involving large vertical pipes owing to the difference in the characteristics of two-phase flows, or flow conditions, between large and small pipes. In this study, we modified the Multi-dimensional Analysis of Reactor Safety KINS Standard (MARS-KS) code using correlations, such as the drift-flux model and two-phase multiplier, developed in a plant-scale air-inflow experiment conducted for a pipe of diameter 600 mm under downward two-phase flow. The results were then analyzed and compared with those based on previous correlations developed for small pipes and pool conditions. The modified code indicated a good estimation performance in two plant-scale experiments with large pipes. For the siphon-breaking experiment, the maximum errors in water flow for modified and original codes were 2.2% and 30.3%, respectively. For the air-inflow accident experiment, the original code could not predict the trend of frictional pressure gradient in two-phase flow as / increased, while the modified MARS-KS code showed a good estimation performance of the gradient with maximum error of 3.5%.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.453-458
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• 2007

The importance of the evaluation and verification of small-size cogeneration system has been emphasized because there is no KS-code related to the small-size cogeneration system. The evaluation method of small-size engine cogeneration system was investigated by the reference of Japan evaluation code, JIS B-8122 and international standard organization, ISO-8528. Evaluation method was introduced such as start-test, rapid-load-up and rapid-load-down, etc. The evaluation method was applied to the 300kW small-size gas engine cogeneration system newly developed. The precise and strict evaluation and verification of the system will help the developing cogeneration system to optimum condition. It will also be a base document of KS-Code.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.4
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• pp.274-279
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• 2009

The flow of a universal system-level design methodology consists of system specification, system-level hardware/software partitioning, co-design, co-verification using virtual or physical prototype, and system integration. In this paper, verification environments based-on SystemVerilog and SystemC, one is native-code co-verification environment which makes prompt functional verification possible and another is SystemVerilog layered testbench which makes clock-level verification possible, are implemented. In native-code co-verification, HW and SW parts of SoC are respectively designed with SystemVerilog and SystemC after HW/SW partitioning using SystemC, then the functional interaction between HW and SW parts is carried out as one simulation process. SystemVerilog layered testbench is a verification environment including corner case test of DUT through the randomly generated test-vector. We adopt SystemC to design a component of verification environment which has multiple inheritance, and we combine SystemC design unit with the SystemVerilog layered testbench using SystemVerilog DPI and ModelSim macro. As multiple inheritance is useful for creating class types that combine the properties of two or more class types, the design of verification environment adopting SystemC in this paper can increase the code reusability.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.191-194
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• 1998

본 논문에서는 OFDM 시스템에서 사용되는 부 반송파의 수와 동일한 길이의 complementary code를 사용하여 각 부 반송파 데이터를 frequency 영역에서 scrambling하는 PAPR 감소 방안을 제안한다. 이 방법은 부 반송파의 수와 동일한 길이의 complementary code 집합을 이용하여 주어진 데이터에 부과해서 PAPR 값이 가장 적은 complementary code를 사용하여 scrambled된 데이터를 송신함으로서 PAPR 값을 감소시키는 방법이다. 수신기에서의 복호를 위하여 Nc개의 complementary code에 해당하는 log2Nc 비트의 code 인덱스를 데이터와 함께 전송한다. 이때 code 인덱스 비트가 PAPR 값에 영향을 주지 않도록 하기 위하여 CODE인덱스와 데이터가 함께 complementary code로 scrambling되어진다. 제안된 이 방법을 사용하면 주파수 대역효율을 높이면서 PAPR 값을 크게 줄일 수 있다.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.2
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• pp.1-10
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• 1997

In this paper, an improved lower bound on the burst-error correcting capability of th ecyclic product code is presented and through the analysis of this new bound clustered cyclic product (CCP abbr.)code is proposed. The CCP code, to improve the burst-error correcting capability, combines the idea of clustering and the transmission method of cyclic product code. That is, a cluster which is defined in this paper as a group of consecutive code symbols is employed as a new transmission unit to the code array transmission of cyclic product code. the burst-error correcting capability of the CCP code is improved without a loss in the random-error correcting capability and performance comparison in the digital video camera records (DVCR) system shows the superiority of the proposed CCP code over conventional product codes.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.5
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• pp.10-15
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• 2010

Good performance of spectral-amplitude-coding optical CDMA can be obtained using codes based upon Hadamard matrices, but Hadamard codes have very restrictive code lengths of $2^n$. In this paper a new code family, namely extended Hadamard code, is proposed to relax the code length restriction and the number of simultaneous users. The improved performance of the proposed system is analysed with the consideration of phase-induced intensity noise(PIIN).

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.8
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• pp.5-9
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• 2011

Spectral-amplitude-coding optical CDMA systems using codes based upon Hadamard matrices have very restrictive code lengths of $2^n$ and high phase-induced intensity noise(PIIN). In this paper a new code family, namely modified Hadamard code, is proposed to relax the code length restriction and the number of simultaneous users. The improved performance of the proposed system is analysed with the consideration of noise.

• Journal of Biosystems Engineering
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• v.27 no.5
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• pp.451-458
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• 2002

This paper introduces that livestock can be effectively managed by an individual electronic identification system. The proposed system was composed of the original code transmitter, receiver, personal computer, micro-processor, and RS485 telecommunications module. In the individual electronic identification system, the signal including encoded information of a milk-cow was transmitted from an original code transmitter to a micro-processor through RS485 telecommunications module. The transmitted signal can be successfully displayed in a personal computer. This system can be managed by 9999 individuals with a original code transmitter. The recognition rate of an individual electronic identification system was 98.5% and also auto-feeder operates very well. an individual electronic identification system was developed for automation of stockbreeding management. To automate the breeding management, it is necessary to obtain and analyze the individual information distinguished from others preferentially.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.3
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• pp.452-460
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• 2008

ALE-complient RFID middleware system receives EPC code data from reader devices and converts the data into URN format data internally. After filtering and grouping, the system sends the resulting URN code to application and(or) users. Meanwhile, not only the types of EPC code are very diverse, but also another new kinds of EPC code can be emerged in the future. Therefore, a method to process all kinds of EPC code effectively is required by RFID middleware. In this paper, a method to process various kinds of EPC code acquired from RFID reader devices in ALE-complient RFID middleware is proposed. Especially, we propose an approach using ontology technology to process not only existing EPC code but also newly defined code in the future. That is, we build an ontology of conversion rules for each EPC data type to effectively convert EPC data into URL format data. In this case, we can easily extend RFID middleware to process a new EPC code data by adding a conversion rule ontology for the code.

• The Journal of Korean Obstetrics and Gynecology
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• v.32 no.1
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• pp.73-84
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• 2019

Objectives: The purpose of this study is to collect and analyze the KCD codes applied to the treatment of 27 postpartum women who had been treated with Korean traditional medicine in a Korean medicine hospital, so that this study may be used as a basic data for setting the direction of postpartum Korean medical treatment research. Methods: It was approved by the Institutional Review Board (IRB) of ${\bigcirc}{\bigcirc}$ University medical center (IRB approval number : WSOH IRB H1708-02-01). Twenty-seven postpartum women who had been treated at ${\bigcirc}{\bigcirc}$ University medical center were received outpatient treatment for two weeks (from September 27, 2017 to January 5, 2018), and the KCD codes applied to the mothers were collected after obtaining the consent. On the day of registration of the study, the fertility, obstetric history and high-risk pregnancies were identified through an interview. Results: 1. The mean age of the 27 subjects was $33.33{\pm}3.99\;years$ old. Among the subjects, 17 mothers (63.0%) were high-risk pregnancy and 10 mothers (37.0%) were normal. 2. Among the 22 major disease categories, 8 categories were used. M code (musculoskeletal system) was used 243 times (70.85%), followed by R code (unclassified symptom) of 51 times (14.87%) and U code (special purpose code) of 23 times (6.71%). 3. The most commonly used code among the ten frequently used codes was M25.57 (joint pain, ankle and foot), a total of 47 times. Of the remaining nine codes, except for R60.1 (systemic edema) and U68.4 (The deficiency of yang in Bi), all codes were M codes (musculoskeletal system). 4. The M code (musculoskeletal system) was the most used major disease category in high-risk group, a total of 159 times. But in specific categories, the most commonly used code was R60.1 (systemic edema), a total of 28 times. 5. In normal group, the M code (musculoskeletal system) was the most used major disease category, a total of 84 times. Also, in specific categories, the most commonly used code was M25.57 (joint pain, ankle and foot), total 29 times. 6. The U code, corresponding to 'the diagnosis of childbirth and other obstetrical medical use', was used 23 times (6.71%), O code three times (0.87%) and Z code two times (0.58%), which was less than 10% of the total number of codes used. Conclusion: When analyzing KCD codes related to Korean medicine treatment for postpartum diseases, it is important to select the KCD codes that reflect the actual clinical state.