• The Journal of Korean society of community based occupational therapy
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• 제9권2호
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• pp.13-22
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• 2019

Objective : The purpose of this technical research is to determine decline of episodic memory by normal aging focucing on object, spatial location, and temporal order memory. Methods : We allocated seventy-seven of healthy adults from twenty to eighty years old, and performed computer-based cognitive tasks which were consisted of the object, spatial location, and temporal order memory. We used OpenSesame(OpenSesame Inc, OR), put ten pictures people normally see in their daily life, and evaluated those aspects through asking the objects types, object spatial locations, and picture temporal orders from 10 sheets of the picture. Results : Object and spatial location memory were not affected by normal aging whereas, temporal order memory significantly decreased with normal aging. Specifically, temporal order memory for in their age of forty was significantly decreased compared with their age of twenty and object memory at their age of eighty was relatively high compared to spatial location and temporal order memory. We found out that temporal order memory worse fastest and object memory lasted longest. Conclusion : In this study, we confirmed characteristics of declines of episodic memory consisting of object, spatial location, and temporal order memory. Notably, we could specifically identify declines of spatial location and temporal order memory with normal aging previous studies investigated on a limited basis using conventional neuropsychological assessments. These findings would be helpful to screen impairment in episodic memory by normal aging and provide an evidence that cognitive intervention for healthy older adults needs to include spatial and temporal aspect of memory.

• Geophysics and Geophysical Exploration
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• 제21권3호
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• pp.139-149
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• 2018

The resistivity monitoring is a practical method to resolve changes in resistivity of underground structures over time. With the advance of sophisticated automatic data acquisition system and rapid data communication technology, resistivity monitoring has been widely applied to understand spatio-temporal changes of subsurface. In this study, a new 4D inversion algorithm is developed, which can effectively emphasize significant changes of underground resistivity with time. To overcome the overly smoothing problem in 4D inversion, the Lagrangian multipliers in the space-domain and time-domain are determined automatically so that the proportion of the model constraints to the misfit roughness remains constant throughout entire inversion process. Furthermore, a focusing model constraint is added to emphasize significant spatio-temporal changes. The performance of the developed algorithm is demonstrated by the numerical experiments using the synthetic data set for a time-lapse model.

• The Journal of the Acoustical Society of Korea
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• 제25권5호
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• pp.239-245
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• 2006

Time-reversal processing (TRP) has been shown as an effective way to focus in both time and space. The temporal focusing properties have been used extensively in underwater acoustics communications. Recently. adaptive time-reversal processing (ATRP) was applied to the simultaneous multiple focusing in an ocean waveguide. In this study. multiple focusing with ATRP is extended to the underwater acoustic communication algorithm for multiple receiving locations. The developed algorithm is applied to the underwater acoustic communication to show, via simulation and real data, that the simultaneous self-equalization at multiple receiving locations is achieved.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제46권1호
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• pp.59-69
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• 2013

Temporal and spatial variation in the freshwater region, created by river runoff, of a small bay, caused by the passage of typhoons was examined using a three-dimensional primitive equation model (the Princeton Ocean Model, POM). Numerical experiments were implemented focusing on temporal evolution in the freshwater region in association with typhoon tracks. The model domain covered most of the estuary around the Nakdong River, including Noksan Bay, where river water is periodically released from upstream (Noksan dam). The model showed that the extension of the freshwater region outside of the bay depended strongly on the tracks of typhoons, specifically the associated wind directions and inner flow fields that are accompanied by new clockwise eddies. The model also showed that entrainment from typhoon passage frequently creates salt wedges in the estuary, indicating that organisms in the bay are biologically and chemically influenced with variation in the freshwater region.

• Journal of KSNVE
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• 제6권4호
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• pp.521-528
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• 1996

Recently, higher speed optical disk drives including computer CD-ROM drives tend to be increasingly demanded to read or write the enormous volume of digital data. To this end, both structure and controller designs of the optical pick-ups should be improved concurrently. In this paper, the pick-up during auto-focusing motion is mathematically modelled retaining all its peculiar features. The model turns out a linear time invariant system suitable for a control design namedH${\infty}$ which ensures robust stability in the presence of system uncertainties. Numerical simulations are performed to demonstrate the robustness with appropriate performance specifications being satisfied. In addition, as the implementation issue of it, procedures of temporal discretization as well as model reduction of the controller are also addressed.

• Archives of design research
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• 제18권3호
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• pp.63-74
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• 2005

Modern society is diversified society and is under complicated situation as the boundary of each area has been disappeared. To understand and accept such complicated situation as widely as possible, it is required to understand interaction. of receiver with intertextual environmental arts as the structure of open text. This study examined interaction of environmental arts in terms of intertextual feature based on experience of receiver on combined element of different space and time, combination of genres. This is the concept of meaning personal experience or situation as receiver participates the process of completing art works, and set the fantasy, post-place and speciality of location and temporal-spatial expression method, as characteristics of intertextuality. Features of such experience elements are used as methodology of analyzing characteristics of each work. Feature of fantasy uses strategy of inducing spatial experience of receiver with dematerialization for post-place and expands the place where events occur with intervention of contingency and event situation. It suggests the spatial-temporal expression method as the features focusing on process and reflecting changes in spatial-temporal continuum and speciality of place emphasizing context of place. In conclusion, environmental arts needs to be deep rooted on complicated existence aspect of receiver beyond metaphysical dimension depending on presence and to accomplish conversion of awareness of supplying bisection of life from that place. By doing so, environmental arts can live textual life as it gets together with all other texts in terms of text dimension and creativity can be reborn as practical creativity in intertextuality rather than uniqueness. Such combination with other areas and acceptance of various aspects of receivers who see and experience this will result to creation of open works which can be create newly over and over again in multi-dimensional aspects.

• Proceedings of the Optical Society of Korea Conference
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• 한국광학회 2003년도 제14회 정기총회 및 03년 동계학술발표회
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• pp.40-41
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• 2003

(self-focusing)을 이용한 커렌즈 모드록킹(Kerr-lens mode-locking； KLM) 방법을 이용하면 간단한 구조를 갖는 공진기로 100 펨토초(femto=10-13) 미만의 레이저 펄스를 생성할 수 있다. KLM 티타늄사파이어(Ti：sapphire) 레이저의 발달로 10 펨토초 영역의 레이저 펄스를 간단하게 생성할 수 있게 되었으며 특히, 넓은 스펙트럼 폭을 가지는 처프거울(chirped mirror)의 사용과 정확한 분산의 보정을 통한 5 펨토초(800 nm 파장의 두 주기에 해당) 영역의 레이저 펄스 생성도 보고되고 있다.

• Journal of the Institute of Electronics and Information Engineers
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• 제49권10호
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• pp.47-53
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• 2012

Time-reversal (TR) precoding focuses the energy of the effective channel in time and improves receive performance of a single tap receiver. Frequency-domain equal-gain-combining (FD-EGC) TR scheme, which works in linear block precoding fashion, has better temporal focusing performance than the traditional TR. Also, the FD-EGC improves receive performance of minimum mean square error receiver with distributed antenna systems (DAS). The detailed receive performance of the FD-EGC was analyzed in our previous work. In this paper, we focused on capacity analysis of the FD-EGC in DAS. We derived a scaling law which shows how the use of multiple antenna can increase the capacity of the FD-EGC precoding compared with that of no precoding. In addition, we analyze the secrecy rate of the FD-EGC which shows how high-rate messages can be transmitted towards an intended user without being decoded by the other users from the view point of information theoretic security.

• The Journal of Society for e-Business Studies
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• 제18권4호
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• pp.273-299
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• 2013

This study attempts to identify user perceived value as a major predictor of the usage of smartphone-based mobile commerce(m-commerce). More specifically, the study conceptualizes user perceived value of smartphone-based m-commerce along three dimensions, such as temporal, functional, and economic values. Moreover, this study proposes service ubiquity and user control that are uniquely defining characteristics of smartphone-based m-commerce and examines how the two variables are associated with the creation of user perceived value. Using a total of 164 data collected on users of smartphone-based mcommerce, we conducted PLS analysis to test the proposed model and hypotheses. The key findings are as follows : First, it has been found that the usage of smartphone-based m-commerce is determined by the three values, such as temporal, functional, and economic values. Particularly, the results show that temporal value is the most influential variable in predicting m-commerce use. Second, the results demonstrate that service ubiquity has a significant positive effect on temporal value, whereas it has no effect on functional value. Finally, user control is positively associated with temporal and functional values. Overall, the results indicate that service ubiquity and user control considerably increase temporal value, thereby accelerating the use of smartphone-based m-commerce. Discussions and implications of the results are provided.

• Journal of Korea Multimedia Society
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• 제13권9호
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• pp.1365-1372
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• 2010

Information of video can be percieved as the form of visual rhythm through temporal ordering systems. The shot, the base unit of video analysis, affects audience psychologicaliy with various temporal combination. Here, psychological stress and density of the story can be adjusted by the point of view shot of character. Acordingly the correlation analysis of shot duration and point of view shot can be useful for visual rhythm research. Identity one of the thriller genre works was selected for analyzing. This works produced by Kyle Cooper, a famous person in the opening sequence field. This works produced by Kyle Cooper, a famous person in the opening sequence field.