• Journal of Astronomy and Space Sciences
• /
• v.27 no.2
• /
• pp.129-134
• /
• 2010

Rain attenuation can cause a serious problem that an availability of space communication link on Ka band becomes low. To reduce the effect of rain attenuation on the error performance of space communications in Ka band, an adaptive coding and modulation (ACM) scheme is required. In this paper, to achieve a reliable telemetry data transmission, we propose an adaptive coding and modulation level using turbo code recommended by the consultative committee for space data systems (CCSDS) and various modulation methods (QPSK, 8PSK, 4+12 APSK, and 4+12+16 APSK) adopted in the digital video broadcasting-satellite2 (DVB-S2).

• Journal of Korean Library and Information Science Society
• /
• v.30 no.3
• /
• pp.295-322
• /
• 1999

The purpose of this study is to identify and present the solution to the problems of KORMARC on Disc, which was produced by the National Library of Korea and is being distributed nationwide. Currently, KORMARC on Disc has reached the serious level of duplicates of input record, error on input data and noise of retrieval. Futhermore, input data is not in accordance with KORMARC Rules for Descriptive Cataloging, thus generating many problems. Of all thing, since current MARC system itself is based on manual system, it does not correspond effectively to the online environment. Accordingly, in order to elevate the quality of KORMARC database, current problems must be resolved, at the same time, korea Machine Readable Cataloging must be modified into a format, more suitable to Machine Readable environment. Consequently, the current study analyzes and identifies problems of data in KORMARC on Disc, at the same time, it examines currently used KORMARC Format and Korea machine Readable Cataloging Rules for descriptive Cataloging as to provide easier usage and guidelines for accurate data inputs.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2003.11b
• /
• pp.557-560
• /
• 2003

In this paper, we developed an editor and running engine for the SoftPLC. LD is the most popular standard IEC 1131-3 PLC language in Korea and used over 90% among the 5 PLC languages. In this paper, we have developed the ISPLC(Intelligent Agent System based Software Programmable Logic Controller). In ISPLC system, LD programmed by a user is converted to IL, which is one of intermediate codes, and IL is converted to the standard C code which can be used in a commercial editor such as visual C++. In ISPLC, the detection of logical error in high level programming(C) is more efficient than PLC programming itself. ISPLC provide easy programming platform to such beginner as well as professionals. The study of code conversion of LD-> U->C is firstly tried in the world as well as KOREA.

• Journal of Korea Multimedia Society
• /
• v.20 no.6
• /
• pp.935-949
• /
• 2017

The purpose of this study was to analyze the characteristics of virtual manipulatives apps that can be used to teach students struggling to learn mathematics. To achieve this goal, ten general characteristics of 23 virtual manipulatives apps were evaluated. The instructional, interface, and interactive design features of apps were also evaluated on five-point scale ratings of 18 items. In addition, SPSS frequency analysis and the correlation between each feature was analyzed. Frequently presented instructional contents among 23 virtual manipulatives apps were geometry, arithmetic operation, number concept and measurement. The frequently presented level of instructional contents was lower grade elementary school and kindergarten age. The frequently presented instructional type was the simulation. Regarding the design features, instructional design was rated as the highest (mean = 3.7); interactive design (mean = 3.6) and interface design (mean = 3.3) were also rated higher than neural. In addition, as the learning strategy was appropriately presented, it was evaluated that there was less screen linkage and content error.

• Journal of Power Electronics
• /
• v.9 no.3
• /
• pp.456-463
• /
• 2009

The paper presents a method for controlling induction motors using a nonlinear internal model control (IMC) approach. The process model and the inverse model are developed in the rotor flux coordinate. The main advantage of the proposed method is that it easily specifies the performance (steady state error, transient response, etc.) and the robustness of the controller by means of the IMC filters. Simulation results illustrate the effectiveness of the proposed method. Results on a real time system show that the control system has good performance and robustness against changes in motor parameters (rotor and stator resistances, rotor and stator inductances, rotor inertia).

• Proceedings of the KIEE Conference
• /
• 1987.07b
• /
• pp.1532-1535
• /
• 1987

In this paper, we propose the algorithm for mask level simulation. The circuit parameters were extracted from the photomask data in format of bitmap. The extracted circuit parameter was transformed into the input file format of SPICE-16. And then the simulation of mask pattern data was carried out the SPICE-16. Thus the error operation of IC due to the mistake of photomask pattern could be prevented.

• Proceedings of the KIEE Conference
• /
• 1987.07b
• /
• pp.1560-1563
• /
• 1987

This paper is concerned with time delay modeling of ED MOS gates which takes into account the slope of input waveform as well as the load condition. Defining the delay time as the time required to charge/discharge the load to the physical reference level, the rise/fall delay times arc derived in an explicit formula in terms of the sum of optimally weighted current unbalances at two end points of voltage transition. The proposed model is computationally effective and the error is typically within 10% of the SPICE results.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39A no.3
• /
• pp.121-126
• /
• 2014

Demand of the data storage becomes more and more growing. This requests the next generation of storage devices to have the dominated storage capability associated with superfast read/write rate. Holographic data storage (HDS) is investigated for a long time and is considered to be a candidate for the future storage system. However, it has two-dimensional intersymbol interference that conventional one-dimensional detection solutions have not yet handled strictly because of the complexity level of system as well as the cost. We propose a new scheme that combines iterative soft output Viterbi algorithm with noise filter for improving the bit error rate performance of HDS.

• Proceedings of the KSR Conference
• /
• 2003.10b
• /
• pp.27-34
• /
• 2003

This Study is about adoption of slab track on the new high speed railway line between Daegu and Busan. While ballast track currently used is easy to construct with low investment, the error margin of rail track occurs in the track due to the repetition load of the train. Therefore, repairs should be carried out all the time to put the railway track at the repair level or less. In addition, noise caused by such repairs has become a new social problem at night. Construction costs for slab track are about 1.3-1.5 times higher than those for ballast track. However, slab track will save labor costs by solving various problems of ballast track. In this regard, it is feasible to adopt slab track on the new high speed railway line between Daegu and Busan.

• Annual Conference on Human and Language Technology
• /
• 2018.10a
• /
• pp.661-664
• /
• 2018

온라인 게시판 글과 채팅창에서 주고받는 대화는 실제 사용되고 있는 구어체 특성이 잘 반영된 텍스트 코퍼스로 음성인식의 언어 모델 재료로 활용하기 좋은 학습 데이터이다. 하지만 온라인 특성상 노이즈가 많이 포함되어 있기 때문에 학습에 직접 활용하기가 어렵다. 본 논문에서는 사용자 입력오류가 다수 포함된 문장에서의 한글 오류 보정을 위한 sequence-to-sequence Denoising Autoencoder 모델을 제안한다.