• Journal of Convergence for Information Technology
• /
• v.11 no.11
• /
• pp.312-326
• /
• 2021

Building on the framework of language socialization [10] in language learning and use, the present study examines the environmental factors involved in four college students' English learning in the situated place of the home during the COVID-19 pandemic. Using narrative inquiry, this study implements a time-series analysis to investigate undergraduates' online English learning in a rural area of northwest China. The data were collected via oral and written narration, semi-structured interviews, and class documents. Leveraging the field-habitus theories, the findings reveal that each of the students had a different habitus in the family field that influenced their English learning at home between March to July of 2020. Ultimately, all four students felt that their habitus made their online English learning ineffective and expressed that they did not wish to continue learning at home. The findings imply that it is important for rural parents to pay more attention to building college students' learning environments and helping students cultivate a strong learning habitus in the family field in northwest China.

• Cross-Cultural Studies
• /
• v.46
• /
• pp.465-495
• /
• 2017

The purpose of this study is to verify whether the concept of time conveys meanings similar to nonverbal communicative elements in foreign language education. This study surveys cultural traits of time from the French cultural education perspective. Anthropologist Edward T. Hall points out that each cultural community has developed a different perception of time and experience, and that time conveys the meaningful message nonverbally similar to the nonverbal elements such as space, gesture, eye movement, and facial expression. I investigated the time experiences of a drinking party in France and in Korea, from a cultural relativistic point of view. The subject of a drinking party was chosen on the ground that a drinking party is highly related to most people's daily lives and it also indicates how they have a relationship with others. I sought a new direction in foreign language cultural education by analyzing how cultural differences between the two communities, especially the relationships between individuals and organisations, ways to separate leisure and labor, and the nonverbal elements, are presented in the two drinking parties.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.32 no.6
• /
• pp.411-419
• /
• 2020

The experiment of unsteady rip current generated at the successive ends of breaking wave crests of honeycomb pattern waves was conducted in a laboratory wave basin, and its time-varying evolution was observed by using ortho-rectified images. The present experiment utilized the generation of a quasi nodal line of the honeycomb-pattern waves formed by out-of-phase motion of two piston-type wavemakers arranged in the transverse direction, instead of the original honeycomb pattern waves which are generated when two wave trains propagate with slightly different wave directions. The velocities of rip current were measured by using the LSPIV (Large-Scale Particle Image Velocimetry) technique. As a result, the unsteady rip current was generated between successive ends of wave crests, and evolved with its shear fluctuations in this experiment. Also, the time series of LSPIV velocity of the unsteady rip current showd its short component due to waves and its long component due to wave-induced currents.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.18 no.1
• /
• pp.115-126
• /
• 2023

Due to the fluctuating random and periodical nature of renewable energy generation power quality disturbances occurred more frequently in power generation transformation transmission and distribution. Various power quality disturbances may lead to equipment damage or even power outages. Therefore it is essential to detect and classify different power quality disturbances in real time automatically. The traditional PQD identification method consists of three steps: feature extraction feature selection and classification. However, the handcrafted features are imprecise in the feature selection stage, resulting in low classification accuracy. This paper proposes a deep neural architecture based on Convolution Neural Network and Long Short Term Memory combining the time and frequency domain features to recognize 16 types of Power Quality signals. The frequency-domain data were obtained from the Fast Fourier Transform which could efficiently extract the frequency-domain features. The performance in synthetic data and real 6kV power system data indicate that our proposed method generalizes well compared with other deep learning methods.

• Journal of Navigation and Port Research
• /
• v.47 no.4
• /
• pp.212-219
• /
• 2023

Vessel Traffic Service (VTS) area presents a complex traffic pattern due to ships entering or leaving the port to utilize port facilities, as well as ships passing through the coastal area. To ensure safe and efficient management of maritime traffic, VTS operators continuously monitor and control vessels in real time. However, during periods of high traffic congestion, the workload of VTS operators increases, which can result in delayed or inadequate VTS services. Therefore, it would be beneficial to predict traffic congestion and congested areas to enable more efficient traffic control. Currently, such prediction relies on the experience of VTS operators. In this paper, we defined vessel traffic congestion from the perspective of a VTS operator. We proposed a method to generate traffic networks using historical navigational data and predict traffic congestion and congested areas. Experiments were performed to compare prediction results with real maritime data (Daesan port VTS) and examine whether the proposed method could support VTS operators.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.26 no.4
• /
• pp.200-217
• /
• 2023

The purpose of this study is to analyze the urban spatial network of Busan in a time-series manner to examine the planning role of centeral area change and spatial management. The analysis method used the ASA(Angular Segment Analysis) technique of the space syntax theory, and the analysis period was divided into three periods from 1937 to 2022, when the Busan urban planning was established. As the result, the center area formed in Nampo-dong and Gwangbok-dong were differentiated and moved to Seomyeon, and then the process of redifferentiated into Yeonsan was confirmed in Seomyeon. It is also room for the center area to move to the western region in the future, and it was possible to identify the center area formed by the policy-set and amenity elements. In addition, we examined the system of urban spatial structure through the intelligibility analysis of space syntax theory, and found that the qualitative interpretation of existing studies and the interpretation from the perspective of space syntax theory were consistent with each other. Through this, it was possible to confirm that the role of the plan for space management.

• Bulletin of the Korean Space Science Society
• /
• 2011.04a
• /
• pp.19.3-19.3
• /
• 2011

1631년 정두원이 명나라로부터 가져온 네 권의 과학서와 한 편의 보고서 가운데, 치력연기(治曆緣起)라는 책과 서양공헌신위대경소(西洋貢獻神威大鏡疏)가 강화도의 외규장각에 소장되고 있었다. 이 점에 유의하여 강화도 외규장각에 소장되어 있었던 천문학 및 수학 관련 서적을 조사해 보았다. 외규장각 소장 도서의 목록에 해당하는 외규장각형지안(外奎章閣形止案)을 조사하여, 소장 도서의 내역과 소장 상태의 변천을 알아낼 수 있다. 그 결과 서양공헌신위대경소는 1791년 신해박해 때 천주교 서적으로 오인되어 소각되었고, 치력연기는 1866년 병인양요 때 프랑스 해군에 의해 소각되었음을 알 수 있었다. 외규장각에는, Napier의 대수(logarithm)에 관한 아이디어가 반영되어 있는 쟈크 로우(Rho)의 주산(籌算)이란 책이 소장되어 있었고, 조선조 양대 물시계에 관한 보고서인 흠경각영건의궤(欽敬閣營建儀軌)와 보루각중수의궤(報漏閣重修儀軌)가 있었으며, 조선 국왕들이 천문에 관해 작성한 어제 및 어필이 소장되어 있었으며, 천문류초(天文類抄)와 천기대요(天機大要)와 같은 널리 사용되던 천문 및 음양학관련 서적이 소장되어 있었다. 특히, 1866년 프랑스 해군에 의해 약탈되어 현재 프랑스 파리 국가도서관에 소장되어 있는 천상열차분야지도는 숙종석각의 탁본으로 추정된다. 현재 10여 개의 탁본이 국내외에 남아 있으나, 최근 프랑스로부터 반환되게 된 외규장각 도서 내역에 천상열차분야지도가 포함되지 못하였다. 이와 관련하여 약간 토의하고자 한다.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.463-466
• /
• 2009

Some strategies for the integrated water management system based on GIS was suggested for the comprehensive and systematic management on the watershed. Contents of database and thematic layers for the related elements with GIS was indicated to estimate the quantity of total pollution loads and to simulate the water quality. Also, functions for the information providing was suggested on the connection with spatial data and attribute data, the search for collected data, the analysis for time series, and the visual presentations. Finally, it was suggested to integrate the existing systems and database structures, and to construct of data warehouse.

• Journal of the Korea Society of Computer and Information
• /
• v.19 no.4
• /
• pp.81-90
• /
• 2014

As mobile devices have become widely used and developed, PC based malwares can be moving towards mobile-based units. In particular, mobile Botnet reuses powerful malicious behavior of PC-based Botnet or add new malicious techniques. Different from existing PC-based Botnet detection schemes, mobile Botnet detection schemes are generally host-based. It is because mobile Botnet has various attack vectors and it is difficult to inspect all the attack vector at the same time. In this paper, to overcome limitations of host-based scheme, we compare two network-based schemes which detect mobile Botnet by applying HMM and SVM techniques. Through the verification analysis under real Botnet attacks, we present detection rates and detection properties of two schemes.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2008.04a
• /
• pp.317-320
• /
• 2008

본 논문에서는 Type-1 퍼지 논리 시스템과 Type-2 퍼지 논리 시스템을 설계하고, 불확실한 정보를 갖는 입력 데이터에 대하여 각각의 성능을 비교한다. Type-1 퍼지 논리 시스템은 외부잡음에 민감한 단점을 가지고 있는 반면, Type-2 퍼지 논리 시스템은 불확실한 정보를 잘 표현할 수 있으며 효율적으로 취급한다. 따라서 Type-2 퍼지 논리 시스템을 이용하여 이러한 단점을 극복하고자 2가지의 모델을 설계한다. 첫 번째 모델은 규칙의 전 ${\cdot}$ 후반부가 불확실성을 표현 할 수 없는 Type-1 퍼지 집합으로 구성된 Type-1 퍼지 논리 시스템을 설계한다. 두 번째는 규칙 후반부만 Type-2 퍼지 집합으로 구성한 두가지의 Type-2 퍼지 논리 시스템을 설계한다. 여기서 규칙 전반부의 입력 공간 분할에는 Min-Max 방법의 균등분할을 사용하고, 규칙 후반부 멤버쉽 함수의 중심 결정에는 입자 군집 최적화(Particle Swarm Optimization) 알고리즘을 사용하여 동정한다. 또한 입력 데이터에 인위적으로 가하는 노이즈의 정도에 따른 각각 모델의 성능을 비교한다. 마지막으로 비선형 모델 평가에 주로 사용되는 가스로 시계열 데이터를 제안된 모델에 적용하고, 실험을 통하여 불확실한 정보를 다루기에 Type-1 퍼지 논리 시스템 보다 Type-2 퍼지 논리 시스템이 효율적이라는 것을 보인다.