• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1545-1548
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• 1997

A Force-refecting hand controller can provide the kinesthetic information obtained from a slave manipulator to the operator of a teleoperation system. This thesis presents the desgn and the analysis of a 6-degree-of-freedom force-reflecting hand controller using fivebar parallel mechanism. The goal of this thesis is to construct a superior hand controller that can provide large workspace and good force-reflecting ability. The forward kinematics of the fivebar paprallel mechanism has been calculated in real-time using three pin-joint sensors in addition to six actuator position sensors. A force decomposition approach is used to comput the Jacobin. To analyze the characteristics of the fivebar parallel mechanism, it has been compared with the other three parallel mechanisms in terms with workspace and manipulability measure. The force-reflecting hand controller using the fivebar parallel mechanism has been constructed and tested to verify the feasibility of the design concept.

• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.744-750
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• 2003

In quantum dynamics of many-body systems, to identify the Hamiltonian becomes more difficult very rapidly as the number of degrees of freedom increases. In order to simplify the dynamics and to deduce dynamically relevant Hamiltonian information, it is desirable to control the dynamics to lie within a reduced space. With a judicious choice for the cost functional, the closed loop optimal control experiments can be manipulated efficiently to steer the dynamics to lie within a subspace of the system eigenstates without requiring any prior detailed knowledge about the system Hamiltonian. The procedure is simulated for optimally controlled population transfer experiments in the system of two degrees of freedom. To show the feasibility of steering the dynamics to lie in a specified subspace, the learning algorithms guiding the dynamics are presented along with frequency filtering. The results demonstrate that the optimal control fields derive the system to the desired target state through the desired subspace.

• Journal of Communications and Networks
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• v.8 no.4
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• pp.401-409
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• 2006

Orthogonal frequency division multiplexing (OFDM) and multiple input multiple output (MIMO) technologies provide additional dimensions of freedom with spectral and spatial resources for radio resource management. Multi-dimensional radio resource management has recently been identified to exploit the full dimensions of freedom for more flexible and efficient utilization of scarce radio spectrum while provide diverse quality of service (QoS) guarantees. In this work, a multi-dimensional radio resource scheduling scheme is proposed to achieve above goals in hybrid orthogonal frequency division multiple access (OFDMA) and space division multiple access (SDMA) systems. Cochannel interference (CCI) introduced by frequency reuse under SDMA is eliminated by frequency division and time division between highly interfered users. This scheme maximizes system throughput subjected to the minimum data rate guarantee. for heterogeneous users and transmit power constraint. By numerical examples, system throughput and fairness superiority of the our scheduling scheme are verified.

• Journal of the Optical Society of Korea
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• v.13 no.2
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• pp.184-192
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• 2009

There are total eight degrees of freedom in designing a three-mirror system. If we correct four kinds of third order aberrations and the system should have the specified effective focal length, the remaining three degrees of freedom can be used for selecting a suitable configuration for a specific application. We suggest an analytic design procedure for a three-mirror telescope system which has a suitably sized secondary mirror and proper separations between mirrors, and is corrected for four kinds of third order aberrations, spherical aberration, coma, astigmatism, and field curvature. Two design examples are shown. One has a compact configuration with off-axial field, the other has relatively long configuration with annular ring field.

• Journal of Korean Association for Spatial Structures
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• v.14 no.1
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• pp.101-108
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• 2014

In order to overcome the key shortcoming of Hamilton's principle, recently, the extended framework of Hamilton's principle was developed. To investigate its potential in further applications especially for material non-linearity problems, the focus is initially on a classical single-degree-of-freedom elasto-viscoplastic model. More specifically, the extended framework is applied to the single-degree-of-freedom elasto-viscoplastic model, and a corresponding weak form is numerically implemented through a temporal finite element approach. The method provides a non-iterative algorithm along with unconditional stability with respect to the time step, while yielding whole information to investigate the further dynamics of the considered system.

• Journal of Power Electronics
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• v.5 no.2
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• pp.166-172
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• 2005

The basic equations of a doubly-fed long-stator linear motor for a shuttle-based railway system are established. They show which degrees of freedom exist for controlling the motor. The ratio of stator and rotor current proves to be an important parameter in determining the design of motors, converters and mechanics.

• Journal of the Korean Society for information Management
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• v.33 no.4
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• pp.293-312
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• 2016

This study aims to shed light on the relationship between information official disclosure and records management in the local government's authority regulations. To that end, analyzed 337 local autonomy laws found in ELIS and the Ministry of Office of Legislation. As a result, it found a link between the 'Public Records Act' in terms of 'records preservation (making minutes)', 'information disclosure procedures for transferred records,' and claims receiving department. 'Record keeping (written minutes)' was similar to that of the 'Public Records Act,' and the 'Claims Receiving Department' mentioned 'Record Management Department.' However, the 'Claims Reception Department' had a strong characteristic of the civil service department, and the 'Public Record Act' did not specify the clause in terms of 'minutes of the minutes.' In 'relation with other laws.'

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.4
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• pp.577-582
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• 1987

A co-operative position control is proposed for two robots manipulation with five degrees of freedom to transfer an object following a specified trajectory, where each manifulator is assumed to change the postrue of its end effector without releasing the object.

• The Journal of the Korea Contents Association
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• v.7 no.4
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• pp.114-122
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• 2007

Recently, Game Rating Board has been established. It is to follow worldwide trend in building up publicity, autonomy and professionalism under the framework to assure freedom of expression. This article analyzed major nation's game rating system, and showed some points to need improvement which are to have more detailed classification in game rating, to modify contents descriptor, to appoint committee members with expertise on game, to revise articles to be capable of misuse, and to become a nongovernmental organization.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.1
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• pp.265-294
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• 2014

The study aims to identify the procedural problems of the archival reference service through Freedom of Information Act. Since FOIA enacted in 1998, there has been a rapid increase of use of government information. However, most of academic users tend to be strongly dissatisfied with the user service. The authors argue that archival reference service through FOIA substantially prevents researchers from using archival records for their research and lower researcher's visits to archival institutions. For this, the study conducted 19 in-depth interviews of academic users and analyzed how FOIA influence academic user's information behaviors based on Strauss and Corbin's grounded theory.