Earticle

본고는 목표어 환경에서 한국어를 학습하고 있는 중국인 학습자의 요청 화행 전략 실현 양상에 대해 숙달도를 중심으로 한 연구이다. 학습자의 숙달도는 한국어능력시험(TOPIK) 성적을 기준으로 중급과 고급으로 구분하였으며 학습자의 요청 전략 수행에 있어 모국어의 영향이 남아 있는지 한국어 모국어 화자에게 근접한지에 대해 분석하고자 한국어 모국어 화자와 중국어 모국어 화자 총 네 집단으로 구성하였다. 연구 도구로는 담화완성형테스트(DCT)를 사용하였다. 연구 결과 구체적인 사회적 변인 즉 요청 상황의 성격, 사회적 힘, 친밀도에 따라 중급과 고급 학습자들의 요청 전략 양상에 차이가 있으며 요청 화행 전략 수행이 학습자의 언어 숙달도와 정비례하지 않다는 것이 밝혀졌다.

The paper reports the effect of the language proficiency on the request speech act realization patterns of KSL learners. The language proficiency is according to the TOPIK(Test of proficiency in Korean) score, divided into two groups as intermediate and advanced level. The insstrument used is a DCT. The result means that the request speech act strategies of KSL learners sometimes are approaching to the KNS, and sometimes is still remained the influence of the learners' native language according to the language proficiency.

The technology competitions of automobile manufacturers are getting hot. The characteristics of the environment friendly automobile are not only lowering the emission of harmful exhaust gas through the change of the power source, but also paying great attention to improvement of the power efficiency. As the market for pure electric vehicles continues to grow, we have analyzed the global technology competitiveness by DCT (Dual Clutch Transmission) patents. Clustering can be classified into five types ; 1) a cluster associated with a dual clutch transmission system, 2) a cluster of a torque transmission device and a reverse speed ratio, 3) a cluster of co-planar sets and dual clutch assemblies related to transmitting devices, 4) Device clusters, and 5) a cluster of synchronizers and clusters to prevent simultaneous operation of dual clutch transmissions. In recent years, demand for pure electric vehicles has been rapidly increasing, and patent applications related to DCT have been steadily increasing for energy efficiency of motor power sources.

Taking a cross-cultural pragmatic approach, this paper compared the speech act of offering advice as realized by Korean L2 learners of English with that of English native speakers. The study investigated pragmatic transfer from L1 Korean while offering advice in L2 English. The study also aimed to examine whether Korean L2 learners’ perception of directness vs. indirectness in the realization of offering advice differs depending on their proficiency. The findings showed that Korean L2 learners of English were not as balanced as native English speakers in the use of indirect strategies of offering advice. The results also revealed that both Korean L2 learners and native English speakers are inclined to use similar strategies for the realization of offering advice. Findings call for further research on pragmatic transfer of the varied English proficiency level and considering appropriate pragmatic teaching methods.

The purpose of the research was to analyze the characteristics which appeared to the process of designing experiment for pre-service elementary teachers. This study were participated 26 pre-service elementary teachers. The findings indicated that first, the researcher figured out the process elements could constructed in 12 elements such as ‘states problem or question, predicts outcome or hypothesizes, lists materials needed, arranges steps in sequential order, lists more than 3 steps, Explore variables and select one or more variables, plans to control variables, plans to measure and observation, plans data collection, plans to repeat testing and tells reason, states plan for interpreting data, states plan for making conclusion based on data, states plan for making conclusion based on data’ but did not figure out 2 elements such as 'defines the terms of the experiment, practice safety'. second, the characteristics of pre-service elementary teachers in the process of designing experiment were as follows; pre-service elementary teachers designed experiments unstructured process listed types and showed the superficial level of the design experiment. The results show that the programs of designing experiment activity should be constructed with the process elements which were concentrated by pre-service elementary teachers, should provide feedbacks to design experiment more accurately.

This study investigates the pragmatic competence and development of learners of Korean as a foreign language (KFL) by examining their performance of the speech acts of request and refusal. It explores the developmental patterns and situational variation for the two speech acts―request and refusal―and also explores the possibility of teaching pragmatics successfully in a KFL setting. Data related to the request and refusal speech acts were collected through Cartoon Discourse Completion Tasks (CDCT). Ten beginner-level and ten intermediate-level students of Korean courses at a university in the United States participated in this study. Nine Korean native speakers (KNS) also participated in the study. The results show that although there was a little development in the intermediate-level KFL students, the students were more focused on the semantic meaning, without clearly understanding the pragmatic function of various Korean expressions. This study suggests that students should practice Korean while imagining various social situations, and they should be explicitly taught how to act appropriately in various common speech act situations.

The purpose of this study is to investigate pragmatic competence on request for Korean college learners. 175 college students were divided into two groups by the test score of English: low level(81) and high level(94). Ten DCT items on request were provided for the students and written down the answers in each situation. Cross-Cultural Speech Act Realization Patterns(CCSARP) coding scheme was used for written responses of request sequences. This study analyzed supportive moves in various aspects. Although the learners used the grounder strategy, they also used the apology strategy as a higher rate. They also made use of the different supportive moves such as disarmer, imposition minimizer, sweeter, preparatory, promise of reward, etc. The frequency rate of other eight strategies except grounder strategy was somewhat different depending on the levels. Most learners in low and high level heavily skewed to the grounder because of their lack of the pragmatic abilities. The findings imply that the teachers in EFL classroom should teach the supportive strategies of request by means of real data.

Among the recent advancements in waveform design for wireless communication, the frequency-modulated orthogonal frequency-division multiplexing (FM-OFDM) has gained attention due to its resilience to phase noise and Doppler spread, as well as its zero-dB peak-to-average power ratio (PAPR). We propose two alternative frequency-time conversion schemes based on discrete cosine transform (DCT) and discrete sine transform (DST) that can potentially supplant discrete Fourier transform (DFT) within FM-OFDM. Extensive simulations demonstrate that FM-OFDM waveforms utilizing DCT and DST can improve link performance compared to those based on DFT. Furthermore, employing frequency-domain spreading with DCT/DST-based FM-OFDM shows additional link performance enhancements. 2024 The Korean Institute of Communications and Information Sciences. Publishing Services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

디지털 비디오 데이터의 효과적인 색인과 검색을 위해서는 비디오 영상 안에 존재하는 자막을 활용하는 것이 매우 중요하다. 본 논문에서는 DCT(discrete cosine transform) 계수와 에지를 이용하여 입력 영상 안에 포함된 자막 을 강건하게 검출하는 방법을 제안한다. 제안된 방법에서는 먼저 입력 영상으로부터 자막이 존재할 것이라고 예상되 는 후보 자막 영역을 수평과 수직 방향의 고주파 특징을 이용하여 검출한다. 그런 다음, 후보 자막 영역에서 자막을 형성하는 영역들만을 에지의 군집화를 통해 추출한다. 그리고 앞에서 추출한 자막 영역에서 배경을 제외하고 문자만 을 추출한다. 마지막으로, 추출된 자막 영역이 비 자막 영역을 포함하지 않고 실제 자막 영역만을 포함하고 있는지 를 신경망을 이용하여 최종적으로 검증한다. 실험에서는 본 논문에서 제안한 자막 영역 검출 알고리즘이 서로 다른 상황에서 자막을 강건하게 추출한다는 것을 여러 가지의 실험을 통해 보여준다.

Utilizing captions is very important for effective video indexing and retrieval in digital video data. In this paper, we propose a method of robustly detecting captions using DCT(discrete cosine transform) coefficients and edges in input images. The suggested method first detects candidate caption regions by using horizontal and vertical high-frequency DCT coefficients. The method then obtains character regions containing captions from candidate regions through edge clustering. Subsequently, we separate captions from background in the obtained candidate region. Finally, we determine actual caption regions among candidate regions using an artificial neural network. Experimental results show that the proposed method can robustly extract caption regions from different input images.

디지털 워터마킹은 멀티미디어 데이터의 소유권 보호를 위해 중요한 역할을 한다. 본 논문은 DCT영역에서 효율적인 시스템적 선형 블록 코드 (SLBC)를 이용하여 디지털 이미지를 위한 새로운 워터마킹 방법을 제안한다. 제안한 SLBC 기반 워터마킹 방법은 에러 보정 능력을 제공하는 {0, 1}의 코드 시퀀스를 생성한 후 {0, 1}의 코드를 {-1, 1}의 바이너리 워터마크 시퀀스로 대치시킨다. 이러한 방법은 더욱더 강력한 보이지 않는 이미지 워터마크를 얻을 수 있으며 바이너리 시퀀스 숫자를 위한 적은 저장장소를 요구한다. 이렇게 재생된 워커마크 시퀀스는 워커마크 임베딩 프로세스와 워터마크 검출 프로세스로 구성된 제안된 워터마킹 시스템의 입력으로 사용된다. 모의 실험 결과, 제안한 방법은 가우시안 잡음, JPEG 압축, 잘라내기, 필터링 등과 같은 다양한 형태의 공격에 대해 잘 알려진 Cox 방법보다 우수한 강인성을 보여준다. 제안한 방법은 10에서 21사이의 유사성 값을 보인 반면, Cox 방법은 같은 공격에 대해 단지 7에서 19의 유사성 값을 보여준다. 이유는 이미지 처리 공격에 의해 발생된 에러가 디코더 단계에서 SLBC에 의해 보정되기 때문이고, 그 결과 강인성이 향상된다.

Digital watermarking plays an important role for copyright protection of multimedia data. This paper proposes a new watermarking method for digital images using efficient systematic linear block codes , SLBC in discrete cosine transform , DCT domain. The proposed watermarking method using SLBC generates a code sequence of {0, 1} that provides error correction capabilities and then replaces it with a binary watermark sequence of {-1, 1} which achieves more robust invisible image watermarks and requires a small storage unit for binary sequence numbers. The generated watermark sequence is then used as an input for our proposed watermarking system which consists of watermark embedding process and watermark detection process. Experimental results indicate that our proposed method outperforms the well-known Cox’s method in terms of robustness against various kinds of attacks such as white Gaussian noise, JPEG compression, cropping, and filtering. Our proposed method achieves similarity values ranging from 10 to 21. This is in contrast to the Cox’s method, which achieves similarity values ranging from only 7 to 19 for the same attacks. This is because errors generated by image processing attacks are corrected with SLBC at the decoder stage, improving the robustness.

In eliciting pragmatics data from a particular learner group, selecting an adequate elicitation method is crucial because different populations react differently to different methods. The present study compared the cartoon discourse completion test (DCT) and the written DCT in eliciting requests from Korean high school students. One hundred high school 2nd graders participated in this investigation. The cartoon DCT group and the written DCT group were each asked to write down what they would say in specific situations. The data was analyzed in terms of response length, strategy types of the head act, external modification, politeness marker and vocabulary. The results showed that the cartoon DCT group significantly produced more words than the written DCT group. In terms of strategy types of head acts, the cartoon DCT group was more direct utilizing the highest percentage of Mood derivable and the lowest of Hints. In addition, the cartoon DCT group produced data closer to a spoken discourse in terms of external modification. That is, the categories of Confirmation check, Introducing oneself, and Hesitation, which are features usually shown in the oral interaction, appeared only in the cartoon DCT data. Also, compared to the written DCT, the cartoon DCT yielded a wider range of external modification use. As for the use of the politeness marker, please, the cartoon DCT group produced a higher number of the marker, and showed a pattern for using it under the social factors embedded in the scenarios while the written DCT group did not. The findings imply that the cartoon DCT is more effective to elicit richer and more real conversation-like speech acts from high school students.

As reproduction of images can be done with ease, copy detection has increasingly become important. In the duplication process, image modifications are likely to occur and some alterations are deliberate and can be viewed as attacks. A wide range of copy detection techniques has been proposed. In our study, content-based copy detection, which basically applies DCT-based features for images, namely, pixel values, edges, texture information and frequency-domain component distribution, is employed. Experiments are carried out to evaluate robustness and sensitivity of DCT-based features from attacks. As different types of DCT-based features hold different pieces of information, how features and attacks are related can be shown in their robustness and sensitivity. Rather than searching for proper features, use of robustness and sensitivity is proposed here to realize how the attacked features have changed when an image attack occurs. The experiments show that, out of ten attacks, the neural networks are able to detect seven attacks namely, Gaussian noise, S&P noise, Gamma correction (high), blurring, resizing (big), compression and rotation with mostly related to their sensitive features.