• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.346-348
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• 2014

VTS 관제사의 가장 기본적인 업무는 모니터링과 동시다발적으로 발생하는 사건을 처리하는 업무라고 할 수 있다. 이러한 모니터링 업무와 동시발생 업무의 관리의 소홀 또는 실패가 VTS 관련 사고로 이어지는 경우가 많다, 그러함에도 불구하고 지금까지는 이 분야에 대한 연구가 부족하였다. 본고에서는 VTS 모니터링 업무와 동시발생 업무 관리의 특성을 분석하고 특히 방해와 산만을 일으키는 요소들을 집중적으로 검토하고 이것이 관제사의 역량에 미치는 영향을 알아보았다. 또한 이러한 문제의 해결책으로 미래계획기억과 분산 기억 시스템 이론을 적용하여 실질적으로 관제사 업무에 도움을 줄 수 있는 방법을 모색하였다. 또한 e-Navigation 과 관련하여 VTS 장비에 장착하여 관제사의 모니터링 업무와 동시다발 발생 업무 관리를 도울 수 있는 도구 개발에 대한 아이디어를 제안하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.5
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• pp.439-444
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• 2005

We investigated the structural and electrical properties of BLT films grown on Si covered with $ZrO_{2}$ buffer layer. The BLT thin film and $ZrO_{2}$ buffer layer were fabricated using a metalorganic decomposition method. The electrical properties of the MFIS structure were investigated by varying thickness of the $ZrO_{2}$ layer. AES and TEM show no interdiffusion and reaction that suppressed using the $ZrO_{2}$ film as a buffer layer The width of the memory window in the C-V curves for the MFIS structure decreased with increasing thickness of the $ZrO_{2}$ layer. It is considered that the memory window width of MFIS is not affected by remanent polarization. Leakage current density decreased by about four orders of magnitude after using $ZrO_{2}$ buffer layer. The results show that the $ZrO_{2}$ buffer layers are prospective candidates for applications in MFIS-FET memory devices.

• Journal of Korean Neurosurgical Society
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• v.30 no.7
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• pp.842-848
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• 2001

Objectives : The mortality rate of subarachnoid hemorrhage(SAH) has been reduced recently due to refinement of microsurgical technique and improved perioperative management. Also, many survivors of SAH show excellent neurological recoveries. However, we found that a high proportion of the survivors do not fully regain their premorbid status in cognitive and memory function. Object of this study is to evaluate which factors might influence on cognitive and memory impairment in ruptured aneurysmal SAH patients. Methods : In this prospective study, a series of 66 patients with aneurysmal subarachnoid hemorrhage(SAH) from 1996 to 1998, most of whom had a "good" or "fair" neurological outcome, were assessed with various tests of cognition and memory function. All patients underwent clipping operation by pterional approach. Right side approach was performed in 16 case and left 21 cases. K-WAIS(Korean-Wechsler Adult Intelligence Scale) was used as method of cognition and memory function test. The time interval between SAH and assessment varied between 4 months and 8 months, averaging 6.2 months. Statistical analyses were carried out for each test score to see whether aneurysm site(A-com : non A-com), route of approach, age and sex, vasospasm, Hunt-Hess grade and Fisher CT group at admission, Glasgow Outcome Scale(GOS) at discharge affect cognitive and memory function. Results : Aneurysm site was not shown to be associated with performance on any test, and the initial grade (Hunt-Hess grade, Fisher CT group) of SAH and vasospasm had only minimal predictive values. The grade at discharge( GOS) was proved to be the best predictor of impairment of cognition and memory function within 1 year after operation. Conclusion : The authors conclude that the diffuse effects of SAH are more important than focal neuropathology in relation to cognitive impairment in this group of patients.

• Korean Journal of Cognitive Science
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• v.27 no.1
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• pp.101-127
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• 2016

The present study was conducted to examine the effect of meta-cognitive strategy and transfer appropriate processing(TAP) on prospective memory performance. In two experiments, encoding strategy for PM target words was manipulated by instructions. Participants who were assigned to meta strategic condition were engaged to rate task difficulty(EOL) in addition to predict their own performance(JOL), while participants in cognitive strategy condition were to remember target words by pleasantness ratings and sentence generation. In experiment1 and experiment 2, all participants in both conditions performed not only TAP ongoing task but also TIP ongoing task. Results revealed the benefit of meta cognition and transfer appropriate processing on PM performance. Furthermore, the benefit of TAP was diminished in cognitive strategy condition. There were no-costs on judgement tasks across conditions. The findings suggest that meta-cognition allows to sustain PM targets and intention without regard to cognitive resource.

• Interaction and multiscale mechanics
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• v.6 no.2
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• pp.197-210
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• 2013

A fundamental trend of processor architecture evolving towards exaflops is fast increasing floating point performance (so-called "free" flops) accompanied by much slowly increasing memory and network bandwidth. In order to fully enjoy the "free" flops, a numerical algorithm of PDEs should request more flops per byte or increase arithmetic intensity. A meshfree/GFEM approximation can be the class of the algorithm. It is shown in a GFEM without extra dof that the kind of approximation takes advantages of the high performance of manycore GPUs by a high accuracy of approximation; the "expensive" method is found to be reversely hardware-efficient on the emerging architecture of manycore.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.387-387
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• 2013

Currently, the flash memory and the dynamic random access memory (DRAM) have been used in a variety of applications. However, the downsizing of devices and the increasing density of recording medias are now in progress. So there are many demands for development of new semiconductor memory for next generation. Magnetic random access memory (MRAM) is one of the prospective semiconductor memories with excellent features including non-volatility, fast access time, unlimited read/write endurance, low operating voltage, and high storage density. MRAM is composed of magnetic tunnel junction (MTJ) stack and complementary metal-oxide semiconductor (CMOS). The MTJ stack consists of various magnetic materials, metals, and a tunneling barrier layer. Recently, MgO thin films have attracted a great attention as the prominent candidates for a tunneling barrier layer in the MTJ stack instead of the conventional Al2O3 films, because it has low Gibbs energy, low dielectric constant and high tunneling magnetoresistance value. For the successful etching of high density MRAM, the etching characteristics of MgO thin films as a tunneling barrier layer should be developed. In this study, the etch characteristics of MgO thin films have been investigated in various gas mixes using an inductively coupled plasma reactive ion etching (ICPRIE). The Cl2/Ar, CH3OH/Ar, and CH4/Ar gas mix were employed to find an optimized etching gas for MgO thin film etching. TiN thin films were employed as a hard mask to increase the etch selectivity. The etch rates were obtained using surface profilometer and etch profiles were observed by using the field emission scanning electron microscopy (FESEM).

• Journal of Korean Academy of Nursing
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• v.42 no.5
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• pp.644-658
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• 2012

Purpose: The purpose of this study was to evaluate the cognitive effects of chemotherapy in patients with breast cancer. Methods: Using several databases, prospective studies were collected up to August 2011. Of 2,106 publications identified, 12 met the inclusion criteria, and 8 studies were used to estimate the effect size of chemotherapy on cognitive impairment. Results: Twelve studies were done since 2005 and most of the research was performed in Europe or North America. Eight studies were used to generate effect size across the cognitive domains of attention/concentration, verbal and visual memory, executive function, visuospatial skill, language, and subjective cognitive function. Each of the cognitive domains showed small effect sizes (-0.02 ~ -0.26), indicating diminished cognitive function for the chemotherapy group compared with non-chemotherapy groups. Conclusion: Finding suggests that breast cancer patients who undergo chemotherapy may experience mild cognitive decline. Further study is needed to generate knowledge and guideline for interventions to address chemotherapy related cognitive impairment in these patients.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.461-468
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• 2018

Objective: Cognitive disturbance is one of the major symptoms of depression and may be improved by treatment with antidepressants. This study aimed to investigate the predictors of cognitive improvement in patients with major depressive disorder (MDD) who were taking antidepressants. Methods: This study included 86 patients with MDD who completed 12 weeks of antidepressant monotherapy. Cognitive symptoms were assessed using the Perceived Deficits Questionnaire-Korean version (PDQ-K), which addresses four domains of cognitive functioning (attention/concentration, retrospective memory, prospective memory, and organization/planning) and was administered at study entry and at the 12-week end point. A variety of demographic, clinical, and treatment-related variables were evaluated as predictors of changes in total and domain scores. Results: All PDQ-K domains showed significant improvement after 12 weeks of antidepressant treatment. More severe initial depressive symptoms, fewer sick-leave days at study entry, and reduced use of concomitant anxiolytics/hypnotics during treatment were significantly associated with greater cognitive improvement. Conclusion: Cognitive symptoms are more responsive to antidepressant treatment in patients with severe MDD. Reduced use of anxiolytics and hypnotics could improve the cognitive functioning of patients with MDD taking antidepressants.

• Wind and Structures
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• v.38 no.2
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• pp.147-160
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• 2024

The aerodynamic force is a significant component that influences the stability and safety of structures. It has unstable properties and depends on computer precision, making its long-term prediction challenging. Accurately estimating the aerodynamic traits of structures is critical for structural design and vibration control. This paper establishes an unsteady aerodynamic time series prediction model using Long Short-Term Memory (LSTM) network. The unsteady aerodynamic force under varied Reynolds number and angles of attack is predicted by the LSTM model. The input of the model is the aerodynamic coefficients of the 1 to n sample points and output is the aerodynamic coefficients of the n+1 sample point. The model is predicted by interpolation and extrapolation utilizing Unsteady Reynolds-average Navier-Stokes (URANS) simulation data of flow around a circular cylinder, square cylinder and airfoil. The results illustrate that the trajectories of the LSTM prediction results and URANS outcomes are largely consistent with time. The mean relative error between the forecast results and the original results is less than 6%. Therefore, our technique has a prospective application in unsteady aerodynamic force prediction of structures and can give technical assistance for engineering applications.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.2
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• pp.177-185
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• 2010

Ray-object intersection is an important element in ray tracing that takes up a substantial amount of computing time. In general, such spatial data structure as kd-tree has been frequently used for static scenes to accelerate the intersection computation. Recently, a few variants of kd-tree traversal have been proposed suitable for the GPU that has a relatively restricted computing architecture compared to the CPU. In this article, we propose yet another two implementation techniques that can improve those previous ones. First, we present a cached stack method that is aimed to reduce the costly global memory access time needed when the stack is allocated to global memory. Secondly, we present a rope-with-short-stack method that eases the substantial memory requirement, often necessary for the previous rope method. In order to show the effectiveness of our techniques, we compare their performances with those of the previous GPU traversal methods. The experimental results will provide prospective GPU ray tracer developers with valuable information, helping them choose a proper kd-tree traversal method.