• Proceedings of the KIEE Conference
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• summer
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• pp.327-329
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• 2004

전력선통신(PLC : Power Line Communication)은 실제 네트워크를 작성할 수 있는 이점은 있지만 이로 인해서 말단의 망 구성이 복잡해지고 여러 부하 장치들의 사용과 운용이 시간과 공간에 따라 전송 특성이 수시로 가변 하는 특성을 가지게 된다. 이러한 특성은 통신시스템 성능상의 다중 경로페이딩의 지연과 성분을 가지게 되므로, 열악한 통신 채널 환경 띤 다중 사용자 간섭에 의한 원인이 된다. 본 논문에서는 이런 원인을 극복하기 위한 한 가지방편으로서, 저간섭 전력선 통신에 적용 가능한 이진 ZCD 확산 코드를 제시하고, 상관 특성을 도출해 봄으로서, 그 유효성을 확인한다.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.29-36
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• 2008

This paper proposes algorithm for the system that can search for an image of a frame unit, and we implement it. A system already inserts in images after generating the cord that mechanical decoding and identification are possible. We are independent of an external noise in a frame unit, and a system to propose at these papers can search for an image recorded by search condition to include recording date, recording time, a recording place or filming course etc. This system is composed by image insertion wealth to insert data to an image to data image code generation wealth, a frame generating data image code you apply a code generation rule to be fixed in order to express to a price to have continued like data entry wealth, GPS locator values and direction price receiving an image signal, image decoding signals and an image search signal to include search condition, and to have continuity from users each of an image. Also, image decoding we decipher about the noise that was already added from the outsides in a telerecording process, a copy process or storage processes inserted in images by real time, and searching image information by search condition. Consequently we implement decoder, and provide the early system that you use, and we easily insert data code among images. and we can search. and maximization can get precision regarding an image search and use satisfaction as we use algorithm to propose at these papers.

• Journal of Practical Engineering Education
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• v.16 no.3_spc
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• pp.259-265
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• 2024

In order to improve the SW convergence capabilities of university undergraduate students, methods to evaluate undergraduate students' code design capabilities should be researched along with the development of related courses. In previous studies, there were qualitative evaluation methods and quantitative relative evaluation methods for code results. In the quantitative relative evaluation method, the number of problem decomposition depth, number of function reuses, and number of functions were measured and evaluated. In this study, an evaluation method that was not presented in previous studies was proposed using the problem of presenting the number of input and output information types when designing code. The evaluation problems proposed in this paper applied up to three types of input information and three types of output information. Through this, five code design evaluation questions were presented and a method to quantitatively calculate code design scores was proposed. Codes from 100 student respondents were collected and analyzed through courses that applied the proposed evaluation method. Through result analysis, the number of problem decomposition depths was proportional to the number of types of input information, the number of function reuses was proportional to the number of types of output information, and the number of functions showed a correlation that was proportional to the total number of types of input and output information. Lastly, by analyzing the distribution of evaluation scores of 100 respondents, we demonstrated that the code design evaluation method according to the five input/output information condition evaluation problems is effective.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.376-382
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• 2014

The purpose of this study is to get the formulas of condensation heat transfer coefficient and pressure drop about the water to develop design program for plate type heat exchangers. The single phase flow of cold side was calculated with the correlation of Ko. Condensation heat transfer coefficient model proposed by Annaiev was used and Lockhart model was used to analyze the pressure drop. The calculation algorithm was proposed to calculate heat transfer rate and pressure drop simultaneously. The prediction errors remained within 20% compared to the commercial code in the working range of the plate heat exchangers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.5
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• pp.957-963
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• 2015

The autocorrelation of an alternative binary offset carrier (AltBOC) signal provides an improved positioning accuracy because of its narrow main-peak. However, The AltBOC signal has a disadvantage that the autocorrelation of the AltBOC signal has multiple side-peaks which incur a severe positioning error. In this paper, we propose a generating method of an unambiguous correlation function for AltBOC signal tracking. Specifically, we first obtain symmetric partial correlation functions, and subsequently, we obtain an unambiguous correlation function by combining them. In numerical results, it is confirmed that the proposed correlation function provides better tracking error standard devation (TESD) performances comparing with the conventional correlation functions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.439-455
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• 2018

This study was designed to analyze the behavior characteristics of people, who have the same or similar Investigative (I) and Enterprising (E) Holland code scores, toward their career commitment. The calculus of the two codes is .16, which means that they are inconsistent and full of oppositions. Especially, the focus of the analysis is whether there are any differences in career commitment between people who have similarly high or low scores of their I and E codes and, if there are differences, what are their characteristics The analysis shows that the participants with high scores of their I and E codes have strong career commitment. They are highly goal oriented and motivated and with a long future time perspective they seek for progress in their careers. Due to their high career expectations and career resilience, they are willing to invest in their careers and put up with a certain level of sacrifice. They place the emphasis on their independence and are not very influenced by the surrounding environment. While the participants with low scores of their I and E codes also perceive the importance of their career commitment, they are very much affected by people and external stimuli. As a result, their efforts in terms of their career commitment are easily disturbed and lowered. The critical factor causing the difference between these two types of people is related to the score of their Social(S) code. This research has the potential to provide improvement points for career counselling.

• The Journal of the Acoustical Society of Korea
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• v.13 no.4
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• pp.40-49
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• 1994

In this paper, we propose methods for improving the performance of word recognition system. The ray stratey of the first method is to apply the inertia to the feature vector sequences of speech signal to stabilize the transitions between VQ cdoes. The second method is generating the new observation probabilities using the transition matrix of VQ codes as weights at the observation probability of the output symbol, so as to take into account the time relation between neighboring frames in DHMM. By applying the inertia to the feature vector sequences, we can reduce the overlapping of probability distribution of the response paths for each word and stabilize state transitions in the HMM. By using the transition matrix of VQ codes as weights in conventional DHMM. we can divide the probability distribution of feature vectors more and more, and restrict the feature distribution to a suitable region so that the performance of recognition system can improve. To evaluate the performance of the proposed methods, we carried out experiments for 50 DDD area names. As a result, the proposed methods improved the recognition rate by $4.2\%$ in the speaker-dependent test and $12.45\%$ in the speaker-independent test, respectively, compared with the conventional DHMM.

• KIISE Transactions on Computing Practices
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• v.22 no.4
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• pp.170-177
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• 2016

Character encoding is a method for changing a document to a binary document file using the code table for storage in a computer. When people decode a binary document file in a computer to be read, they must know the code table applied to the file at the encoding stage in order to get the original document. Identifying the code table used for encoding the file is thus an essential part of decoding. In this paper, we propose a method for detecting the character code of the given binary document file automatically. The method uses many techniques to increase the detection rate, such as a character code range detection, escape character detection, character code characteristic detection, and commonly used word detection. The commonly used word detection method uses multiple word database, which means this method can achieve a much higher detection rate for multi-language files as compared with other methods. If the proportion of language is 20% less than in the document, the conventional method has about 50% encoding recognition. In the case of the proposed method, regardless of the proportion of language, there is up to 96% encoding recognition.

• KIISE Transactions on Computing Practices
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• v.23 no.3
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• pp.188-193
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• 2017

In this paper, we propose automatic OpenCL optimization techniques that offer the best performance for image processing programs on any hardware system. Developers should seek a proper way of parallelization and an appropriate work-group size for the architecture of target compute devices to achieve the best performance. However, testing potential devices to find them is both time-consuming and costly. Our techniques automatically set up hardware-optimized parallelization and find a suitable work-group size for the target device. Furthermore, using OpenCL does not always provide better performance in image processing. Hence, we also propose a way to automatically search for a threshold image size to allow image processing programs to decide whether or not to use OpenCL. Our findings demonstrate that out techniques improve the image processing performance significantly.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7C
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• pp.921-930
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• 2004

In this paper, a robust video transmission system is proposed. To effectively prevent the corruption of video stream and its propagation in spatial and temporal domains, a version of turbo code, so-called as byte-aligned variable-length turbo code, is applied. Protection performance of the proposed turbo code is first evaluated by applying it to GOB-based variable-size ITU-T H.263+ video packets, where the protection level is statically controlled based on the joint source-channel criteria. This protection is then extended to support the adaptation of code ratio to best match the time-varying channel condition. The time-varying Rayleigh fading channel is modelled considering the correlation of the fading channel. The resulting performance comparison with the static turbo code as well as the conventional RCPC code clearly demonstrates the possibility of the proposed adaptation approach for the time-varying correlated Rayleigh-fading channel.