• Nuclear Engineering and Technology
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• v.19 no.4
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• pp.310-316
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• 1987

A successive iteration method to calculate the λ-modes of the diffusion equation was developed. The 2-group, 3-dimensional computer code MOGEN was developed to implement this method, The accuracy of the method was demonstrated using 2-dimensional bare homogeneous rectangular reactor. The numerical solution shows good agreement with the analytic solution in terms of eigenvalue and eigenfunction As for the standard CANDU-600 reactor, the 2-dimensional modes were generated and these represent the conventional mode characteristics well. Finally, application of theλ-mode in reactor engineering problems is described briefly.

• STI Policy Review
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• v.8 no.2
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• pp.23-48
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• 2017

This article advocates for a Mode 3 science policy. Compared to the university research-based Mode 1 knowledge production system and the knowledge application-centric Mode 2 innovation system, Mode 3 can be defined as a system that integrates both Mode 1 and Mode 2-type knowledge production models. In this article, based on the major characteristics of the Mode 3 scientific knowledge production system, I agree with the advocates of Mode 3 that constructing a knowledge society requires an inclusive form of knowledge production and innovation system through the democratization of knowledge production as well as the promotion of social values. Moreover, the mechanisms for creating accountable innovation in the Mode 3 system should be given more attention from the science research and policy communities to make public policy for scientific and technological innovation more reflective of social changes. Similar to the ways that the Mode 1 and Mode 2 scientific knowledge production approaches have influenced the development of science policy models, the Mode 3 scientific knowledge production approach, or Mode 3 science, also has the potential to shape a new science policy model. I will refer to this as Mode 3 science policy. In an effort to conceptualize the democracy- and society-centric Mode 3 science policy model, I will articulate science policy strategies in four science policy domains in South Korea from the context of the Mode 3 science approach. These include (1) evaluation of publicly-funded research activities, (2) valorization of scientific knowledge (that is, enhancement of the value of scientific knowledge through governmental action), (3) development of a science policy decision-making support system, and (4) anticipatory foresight of science, technology and society. When adopting and implementing a Mode 3 science framework, one progressive change is to increase socially desirable innovation such as responsible innovation.

• Bulletin of the Korean Space Science Society
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• 2005.04a
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• pp.133-137
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• 2005

This paper describes the design and performance verification of a pitch momentum bias control system being built by students at the Space System Research Laboratory(SSRL). HAUSAT-2 ADCS(Attitude Determination and Control of Subsystem) op-elation mode is divided into two parts, initial mode and on-orbit mode. This paper describes design of the HAUSAT-2 performance of attitude control results using pitch momentum bias control method in initial mode and on-orbit mode and momentum dumping method.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1392-1395
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• 2004

In order to successfully develop attitude and orbit control subsystem(AOCS), AOCS engineer performs hardware selection, controller design and analysis, control logic and interface verification on electrical test bed, integrated system test, polarity test, and finally verification on orbit after launching. Attitude and orbit control subsystem for KOMPSAT-2 consists of standby mode, sun mode, maneuver mode, science mode, and power safe mode to stabilize and to control the spacecraft for performing the mission. The sun mode is usually divided into sun point submode, earth search submode and safe hold submode. The maneuver mode is divided into attitude hold submode and ${\triangle}$ V submode, while the science mode divided into science coarse submode and science fine submode. Moreover, it is added to back-up mode which uses wheels as an actuator for sun mode and maneuver mode. In this paper, we describe the controller design process and the performance of the design results with respect to the sun mode and the maneuver mode based on thrusters as an actuator using on flexible model.

• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.355-358
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• 2008

In the current GPON market and standard, the line bit rate requirement is changing from 1.25 Gbps to 2.5 Gbps. We fabricate a 2.5 Gbps burst-mode receiver with commercially available blocks and optimize it with an APD bias control. A burst-mode measurement setup is made for the full compliance test with the GPON standard. The device meets the partially defined 2.5 Gbps specs in the current ITU G.984.2 standard, also, supports 1.25 Gbps specs for the coexistence issue in an access network. The full-compliant measurement values can be used as a guideline for fixing "for further study" specs in the current GPON standard at 2.5 Gbps.

• International Journal of Aeronautical and Space Sciences
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• v.6 no.1
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• pp.77-88
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• 2005

KOMPSAT-2 is the second Korean earth observation satellite after KOMPSAT-l: the 1 meter GSD cartographic capability and planning to launch at the end of 2005 by ROKOT launch vehicle. The dedicated AOCS operational modes are designed for KOMPSAT-2 based on KOMPSAT-l experience All of AOCS operational modes requires gyro information. To compensate this drawback, Power Safe Mode is designed and implemented. Successfully AOCS on-board software is developed and extensively verified through a nonlinear simulation process. The simulation results of Power Safe Mode and Science Fine Submode are provided to demonstrate its functionality as well as its performance.

• ETRI Journal
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• v.39 no.3
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• pp.336-344
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• 2017

In this paper, we propose a convenient microwave orbital angular momentum (OAM) mode generation and multiplexing method operating in the 18 GHz frequency band, based on a $2{\times}2$ uniform circular array and a $4{\times}4$ Butler matrix. The three OAM modes -1, 0, and +1 were generated and verified using spatial S-parameter measurements; the measured back-to-back mode isolation was greater than 17 dB in the full 17 GHz to 19 GHz range. However, the radiated OAM beam centers were slightly dislocated and varied with both frequency and the mode index, because of the non-ideal characteristics of the Butler matrix. This resulted in mode isolation degradation and transmission distance limitations.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.69-75
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• 2019

Remotely Piloted Aircraft (RPA) controls as a type of unmanned aerial vehicle (drone) is growing rapidly and its flight controller stick disposition is required standardization. We should standardize RPA drone flight control disposition because the flight pilot of RPA is hard to be trained so the flight controller stick differences impairs safety and wastes time and effort of flight controller industry. So this study researches the on-going standardization of RPA drone flight control disposition in Korea and foreign countries. Also this paper analyzes and researches of expert about RPA drone flight controller function and application of flight control mode. I accomplished expert research about standardization plan of unmanned flight control mode and confirm the necessity. Nowadays mode1 and 2 are mostly used in Korea so I carried out preference investigation for two modes. There were 4 preferences choices of RPA drone control mode necessity (importance) and recommendation of standardization modes. They answered that necessity of standardization is important considering pilot training, flight safety and positive development of drone industry. The result of standardization mode preference is that they prefer mode 2 (drone maker 86%, training facilities and research facilities 58%, government bureau 60%). Overall preference result shows that mode 1 24%, mode 1&2 16%, mode 2 60%. So they preferred mode 2 by 60%. The differences between two modes are the direction of throttle and pitch. Direction of throttle and pitch operate opposite way. They prefer mode 2 because mode 2 has similarities of manned flight control mode. Significance of this study is that it showed the necessity of standardization and flight control preference in a quantitative way. It will help drone standardization in related industries and development direction near future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.114-127
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• 2016

The competition among nations has been extended to competition between localities, and the importance of knowledge activities in local areas is being emphasized. To contribute to the nurturing of highly qualified professionals and the development of local industry, the Korean government established the S&T-centric research universities including KAIST in 5 local areas. These S&T-centric research universities are top notch research centers and educational environments in Korea. However, it has been pointed out that their ability to act as local innovation hubs is limited. Accordingly, this study conducted an empirical analysis on the outcomes of the S&T-centric research universities by dividing them into two categories, Mode 1 and Mode 2, and comparing them with those of other general universities. It was found that the outcomes of the S&T-centric universities were higher in Mode 1, but lower in Mode 2, than those of the general universities. Furthermore, the S&T-centric universities are not connected very much to the region's specialized industries. It was difficult to find any evidence that the S&T-centric universities differ from the other universities in terms of their outcomes or activities as they were initially envisaged.

• ETRI Journal
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• v.31 no.5
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• pp.610-612
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• 2009

We present intra-mixture prediction (IMP) mode for intra prediction and an enhanced estimation method for most probable mode (MPM). IMP mode supports more flexibility in intra prediction by mixing $4{\times}4$ blocks and $8{\times}8$ blocks in one macroblock, while the enhanced MPM estimation extends the number of referenced neighboring blocks and efficiently uses their prediction modes depending on their positions. Simulation results show that the combination of both proposed methods provides a bit reduction in the Bj${\phi}$ntegaard delta bitrate by an average of 2.56% compared to H.264/AVC.