• Research in Mathematical Education
• /
• v.15 no.2
• /
• pp.197-208
• /
• 2011

By using the recording and quantitative analysis of two videos about "The multiplication and division of the Fractions" and the "Flanders Interaction Analysis System," we classified the teachers' language of instruction in algebra classroom and also analysis the language of instruction in the different teaching process. The results after the analysis as follows: (1) The proportion of time was taken in teachers' language of instruction is high and vary in types, most of the teachers' language is teachers' question; (2) In the different teaching process, the proportion of time was taken in teachers' language of instruction is different; (3) Teachers attached importance to explain the example and had the similar teaching strategy, but the teachers' language is different; (4) In the practice process, teachers placed importance on exploring the tough question and its teaching strategies are different. The teachers' questions are the main teachers' language of instruction.

• Journal of Korea Society of Industrial Information Systems
• /
• v.27 no.2
• /
• pp.35-44
• /
• 2022

In this paper, we propose an intra-picture prediction method by a quadratic surface modeling method for depth video coding. The pixels of depth video are transformed to 3D coordinates using distance information. A quadratic surface with the smallest error is found by least square method for reference pixels. The reference pixel can be either the upper pixels or the left pixels. In the intra prediction using the quadratic surface, two predcition values are computed for one pixel. Two errors are computed as the square sums of differences between each prediction values and the pixel values of the reference pixels. The pixel sof the block are predicted by the reference pixels and prediction method that they have the lowest error. Comparing with the-state-of-art video coding method, simulation results show that the distortion and the bit rate are improved by up to 5.16% and 5.12%, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.291-292
• /
• 2014

High-speed video transmission modes of master bridge IC are implemented, which supports MIPI (Mobile Industry Processor Interface) DSI (Display Serial Interface) standard. MIPI DSI master bridge IC sends RGB data and various commands to display module (slave) in order to test it. The master bridge IC consists of buffers storing video data of two lines, packet generation block, and D-PHY layer that distributes packets to data lanes and transmits them to slave. In addition, it supports four bpp (bit per pixel) formats and three transmission modes including Burst and Non-Burst (Sync Events, Sync Pulses types). The designed bridge IC is verified by RTL simulations showing that it functions correctly for various operating parameters.

• Journal of Advanced Navigation Technology
• /
• v.25 no.1
• /
• pp.115-123
• /
• 2021

Pine nuts are Korea's representative nut forest products and profitable crops. However, pine nuts are harvested by climbing the trees themselves, thus the risk is high. In order to solve this problem, it is necessary to harvest pine nuts using a robot or an unmanned aerial vehicle(UAV). In this paper, we propose a deep learning based detection method for harvesting pine nut in UAV aerial images. For this, a video was recorded in a real pine forest using UAV, and a data augmentation technique was used to supplement a small number of data. As the data for 3D detection, Unity3D was used to model the virtual pine nut and the virtual environment, and the labeling was acquired using the 3D transformation method of the coordinate system. Deep learning algorithms for detection of pine nuts distribution area and 2D and 3D detection of pine nuts objects were used DeepLabV3+, YOLOv4, and CenterNet, respectively. As a result of the experiment, the detection rate of pine nuts distribution area was 82.15%, the 2D detection rate was 86.93%, and the 3D detection rate was 59.45%.

• Journal of Digital Contents Society
• /
• v.16 no.5
• /
• pp.775-781
• /
• 2015

EBS started 2HD MMS experimental broadcasting for the first time in Korea on Feb. 11, 2015. It uses the picture compression technique based on MPEG-2 CODEC, and applies the result of the experiment about variable bit rates and changes according to the scanning types, 1080i and 720p. But when changing channels, the delay in displaying picture occurs because of the operation of the variable GOP on MMS broadcasting, which optimizes image quality by application variable bit rates. In this study, verified the relationship between the decoding time of I frames and the GOP set in the encoding step by experimenting and analyzing ON-AIR TS. By using the verification data and adjusts the Encoder GOP parameters, improved the different video display time delays according to the scanning mode 1080i and 720p.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.3 no.2
• /
• pp.69-80
• /
• 1999

Recently in telecommunication, BISDN ( Broadband Integrated Service Digital Network ) has received considerable attention for its capability of providing a common interface for future communication needs including voice, data and video. Since all information in BISDN are statistically multiplexed and are transported in high speed by means of discrete units of 53-octet ATM ( asynchronous Transfer Mode ) cells, appropriate traffic control needs. For traffic shaping of voice, the output cell discarding scheme has been proposed. We analyze the scheme with a MMPP/$D_1$, $D_2$/1/B queueing system to obtain performance measures such as loss probability and waiting time distribution.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.2C
• /
• pp.132-140
• /
• 2007

In this paper, we proposed a new technique to encode and decode the digital hologram. Since the digital hologram (or fringe pattern) is generated by interference of light, it has much different property from natural 2D (2 dimensional) images. First, we acquisite optical-sensed or computer-generated hologram by digital type, and then extract a chrominance component. The extracted digital hologram for coding is separated into segments to use multi-view properties. The segmented hologram shows the similar characteristics with picturing an object with 2D cameras in various point of view. Since fringe pattern is visually observed like as noise, we expect that the fringe pattern has poor coding efficiency. To obtain high efficiency, the segment is transformed with DCT (Discrete Cosine Transform) which resembles hologram generation process with high performance. Each transformed segment passes the 3D scanning process according to time and spatial correlation, and is organized into a video stream. Since the segment which correspond to frame of a video stream consists of the transformed coefficients with wide range of value, it is classified and re-normalized. Finally it is compressed with coding tools. The proposed algorithm illustrated that it has better properties for reconstruction of 16 times higher compression rate than the previous researches.

• Review of KIISC
• /
• v.2 no.4
• /
• pp.37-47
• /
• 1992

이 논문에서 우리는 여러 가지 분할 항등식을 유도했고 제한된 분할에 관한 새로운 항등식을 증명하고, 분할의 기본적인 이론과 분할함수(Partition Number Function)가 다항식 함수가 아니라는 것을 보이며, n의 분할의 수 p(n)에 대한 ㅎ계(Lower Bound)를 얻기 위해 Stirling의 n !에 대한 근사값을 소개한다. 그리고Hardy-Ramanujan 공식, Euler 항등식과 p(n)의 순환식을 유도하며, 그리고 d$_{m}$ (n)이 n을 m개의 부분으로 분할하는 분할의 수를 나타낼 때 우리는 d$_{m}$ (n) 에 관한 일반적인 공식을 p(n)과 함께 행렬식의 형태로 표현한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2001.10b
• /
• pp.454-456
• /
• 2001

본 논문에서는 비디오 영상열 내에 컴퓨터가 생성한 가상의 3D 영상을 이음새 없이 추가하기 위한 문제에 초점을 맞추고 있다. 2단계의 견고한 통계적인 메소드는 추적된 커브들의 모델-영상 대응점으로부터 보다 정확한 자세를 평가하기 위하여 자세 계산을 위해 사용되었다. 또한, 관점의 정확성 향상을 위하여 두 개의 연속하는 영상들간에 매치될 수 있는 핵심점을 카메라 움직임에 대한 상관관계 함수로 사용하여 매칭 에러와 reprojection 에러를 포함한 비용함수를 최소화함에 의해 관점을 향상시킨다. 비디오 영상내 객체 영상과 가상의 3D 영상간에 발생하는 폐색 공간문제를 해결하기 위하여 반 자동 알고리즘을 제안하였다.

• The Journal of Engineering Research
• /
• v.2 no.1
• /
• pp.39-47
• /
• 1997

This paper presents a single board digital signal processing system which can perform two-dimensional (2-D) digital infinite impulse response (IIR) filtering in realtime. We have developed an architecture to provide not only the necessary computational power but also a balance of the system input/output and computational requirements. The architecture achieves large system throughput by using highly parallel processing at both the system and processor levels. It reduces system data communication requirements significantly by taking advantage of a custom-designed processor and by providing each processor with its own input and ouput channel. After system initialization, almost 100 percent of the time is used for data processing. Data transfers occur concurrently with data processing. The functional level simulation reveals that the system throughput can reach as high as one pixel per system cycle. With only 10MHz clock frequency system, it can implement up to fourth order 2-D IIR filters for video-rate data ($512\times512$ pixels per frame at 30 frames per second). If we increase the system frequency, the system can be used for the preprocessing and postprocessing of video signal of HDTV.