• Journal of Korean Ophthalmic Optics Society
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• v.19 no.3
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• pp.407-412
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• 2014

Purpose: It is investigated whether the time division system can extend the field without diplopia for people with homonymous hemianopia. Methods: The time division system was manufactured by a modified mini fan and a black cardboard. In order to verify the effectiveness of the equipment, subjects with and without the equipment took part in the experiment to bisect the space and to recognize letters. Results: Subjects with and without the equipment showed +8.91 and +18.14 degrees in the experiment to bisect the space. In the experiment reading the letters and numbers with the equipment, there were 9 percentage point increase in $4{\times}4$ charts and 15 percentage point increase in $6{\times}6$ charts. It turned out that there was a remarkable improvement for the worst group for reading the charts. Conclusions: The time division system is effective in the mobility and orientation for people with homonymous hemianopia.

• The Journal of Engineering Research
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• v.2 no.1
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• pp.73-82
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• 1997

In this paper, we examine design trends in the development of distributed real-time system. Many real-time systems developed over the last ten years share common characteristics including use of communications, imprecise computations, the object-oriented paradigm, multiprocessor node hardware, dynamic time-driven scheduling and the inclusion of fault tolerance mechanisms. By examining the major design decisions made in previous systems, the best attributes of these systems can be coalesced together to form the "ideal" real-time system. This paper examines such a system and the advantages and disadvantages of the design decisions involved.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.249-258
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• 2010

This study seeks to improve NFRDI Serial Oceanographic observation (NSO) system which has been operated at current observation stations in the Korean Seas since 1961 and suggests the direction of NSO for practical use of Korean operational oceanographic system. For improvement, data handling by human after CTD (Conductivity-Temperature-Depth) observation on the deck, data transmission, data reception in the land station, and file storage into database need to be automated. Software development to execute QA/QC (Quality Assurance/Quality Control) of real-time oceanographic observation data and to transmit the data with conversion to appropriate format automatically will help to accomplish the automation. Inmarsat satellite telecommunication systems with which have already been equipped on board the current observation vessels can realize the real-time transmission of the data. For the near real-time data transmission, CDMA (Code Division Multiple Access) wireless telecommunication can provide efficient transmission in coastal area. Real-time QA/QC procedure after CTD observation will help to prevent errors which can be derived from various causes.

• International Journal of Aeronautical and Space Sciences
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• v.6 no.1
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• pp.52-60
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• 2005

The CFD coupled aeroelastic analyses have significant advantages over linear panel methods in their accuracy and usefulness for the simulation of actual aeroelastic motion after specific initial disturbance. However, in spite of their advantages, a heavy computation time is required. In this paper, a method is discussed to save a computational cost in the time domain aeroelastic analysis based on the system identification technique. The coefficients of system identification model are fit to the computed time response obtained from a previously developed aeroelastic analysis code. Because the non-dimensionalized data is only used to construct the model structure, the resulting model of the unsteady CFD solution is independent of dynamic pressure and this independency makes it possible to find the flutter dynamic pressure without the unsteady aerodynamic computation. To confirm the accuracy of the system identification methodology, the system model responses are compared with those of the CFD coupled aeroelastic analysis at the same dynamic pressure.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.2
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• pp.201-209
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• 2023

Time comparison techniques are required for generating and keeping Coordinated Universal Time (UTC) and to distribute standard clocks. These techniques play an important role in various fields, including science, finance, military, and communication. Among these techniques, Two-Way Satellite Time and Frequency Transfer (TWSTFT) ensures a relatively high accuracy, with a time comparison accuracy at a nanosecond level. However, TWSTFT systems have some limitations, such as the dependency on extra network links. In this paper, we propose an improved method for TWSTFT system operation and design a message structure for the suggestion. Additionally, we estimate the data rate and redundancy for the new TWSTFT signal with the designed message structure.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.483-484
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• 2007

In this paper, we consider the input-output transformation for the time-varying linear system and get the time-invarying linear system. And we present the necessary sufficient condition for the I/O transformation. The transformed system represent the system with the multiple integral. We verify the proposal algorithm via the example and examine.

• 제어로봇시스템학회:학술대회논문집
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• 1986.10a
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• pp.184-187
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• 1986

A time-division-mutiplexed switching system is implemented for connecting various computers and terminals in the laboratory environment.

• Journal of Trauma and Injury
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• v.28 no.4
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• pp.241-247
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• 2015

Purpose: To evaluate the influence of how the trauma care system is applied on the management of trauma patients. Methods: We divided the patients into a pre-trauma system group and a post-trauma system group according to the time when we began to apply the trauma care system in our institution. We compared the general characteristics, injury severity score, initial response time to the trauma patients, number of preventable deaths, and clinical outcomes between the two groups. Results: The numbers of patients in the pre-trauma system group and the post-trauma system group were 188 and 257, respectively. No differences in the patient's median ages, trauma scores (ISS, RTS, TRISS) and proportions of severe trauma patients (ISS>15) were observed between the two groups. The number and the proportion of patients who were admitted to our hospital were increased in the post-trauma system group. The time interval from trauma CP activation to emergency surgery or angio-embolization, and the patient's time spent in emergency room were shortened in the post-trauma system group. However, the lengths of the ICU stay and the hospital stay, and the number of in-hospital mortalities were not improved in the post-trauma system group. In severe trauma patients (ISS>15), there were no differences between the two groups in the number and the proportion of admitted patients, and the time interval from trauma CP activation to performing a diagnostic and therapeutic procedure was not shortened in the post-trauma system group. Conclusion: Application of the trauma care system has shortened the time between the initial response and patient management. However, this improvement was not enough to result in better clinical outcomes. More trauma physicians, multidisciplinary cooperation, and a well-organized trauma management process will be needed if the maximum efficacy of the trauma system is to be achieved.

• Journal of Korea Multimedia Society
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• v.17 no.4
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• pp.433-440
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• 2014

Wireless communication offers the flexibility to the node movement at the spatial dimension more than the wire communication not only in IP architecture but also in Content-Centric Networking. Although it gives such advantage, the intra-domain movement of a node especially the data source node affects the communication to the access point node which in the end affects the acceptance ratio of the client node that requests the data packets from the data source node. In this paper, we use time-division access method to maintain the acceptance ratio of the client node as the effect of the intra-domain data source node movement in Content-Centric Networking. The simulation result shows that the acceptance ratio of the client node can be maintained using the time-division access method as long as the interval access time is less than the coherence time.

• Journal of Radiation Industry
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• v.4 no.1
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• pp.85-89
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• 2010

The radioactive experiments are carried out for diagnosis of a variety of industrial processes in terms of the operation condition and the efficiency by measuring the residence time distribution. However, it is not easy to interpret the residence time distribution using the conventional methods when the flow rate is not constant and a number of processes are coupled in a complicated manner. In these cases, they can be analyzed by describing the system with mathematical models that can be defined with the state-space equations. In this paper, the residence time distribution of sludge was measured with a radiotracer, $^{46}Sc-EDTA$, in the digester of which the flow rate varies with time. The digester was assumed as a linear time variant system since the flow rate changed during the experiment and the operation efficiency of the digester was calculated by applying the state-spae equations.