• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2006년도 춘계학술대회 학술발표 논문집 제16권 제1호
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• pp.245-248
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• 2006

A particle filter is one of the most famous filters. The reason why the particle filter is widely used is that particle deals with the state estimation problem for not only linear models with Gaussian noise but also the non-linear models with non-Gaussian noise and it receives great attention from many engineering fields. In the point of view state estimator, particle filter is feedforward observer. According to the characteristic of dynamic system, the feedforward observer can estimate real state. However, the speed of convergence of feedforward observer between the actual state and the estimated state cannot be satisfied. Since the particle filter is a sort of feedforward observer, the convergence speed of particle filter is slow, and the particle filter cannot estimate actual state like particle collapse problem. In order to overcome the limitation of particle filter as a kind of feedfoward estimator, we propose a new particle filter which has feedback term, called particle filter with feedback. Our proposed method is analyzed theoretically and studied by computer simulation. Comparisons are made with other filtering mehod.

• 한국지반공학회논문집
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• 제19권1호
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• pp.77-92
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• 2003

사질토에서의 한계상태정수 결정시 근본적인 물리적 과정들과 고유적 인 한계성들을 파악하기 위하여 일련의 표준삼축시험을 실시하였다. 시험결과에 의하면, 주어진 흙에 대하여 한계상태마찰각은 배수조건에 상관없이 일정한 반면에, e-log p＇공간상에서의 한계상태선은 주로 표준삼축시험에서 충분치 못하게 도달하는 변형률과 비배수시험에서의 변형률 국지화효과 때문에 배수조건에 따라 다른 결과를 보였다. 실내시험을 통하여 한계상태정수를 산정하는 최선의 방법은 균일하고 느슨하게 성형된 시료를 배수조건하에서 전단하는 것으로 나타났다. 더불어 배수시험에서 다일러턴 시효과나 변형률 국지화효과를 피할 수 있는 시험을 계획하기 위한 참고상태정수를 제시하였다.

• 한국정밀공학회지
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• 제25권12호
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• pp.89-99
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• 2008

In this paper, the position tracking control problem of the servo system with nonlinear dynamic friction is issued. The nonlinear dynamic friction contains a directly immeasurable friction state variable and the uncertainty caused by incomplete parameter modeling and its variations. In order to provide the efficient solution to these control problems, we propose the composite control scheme, which consists of the robust friction state observer, the FNN approximator and the approximation error estimator with sliding mode control. In first, the sliding mode controller and the robust friction state observer is designed to estimate the unknown internal state of the LuGre friction model. Next, the FNN estimator is adopted to approximate the unknown lumped friction uncertainty. Finally, the adaptive approximation error estimator is designed to compensate the approximation error of the FNN estimator. Some simulations and experiments on the servo system assembled with ball-screw and DC servo motor are presented. Results show the remarkable performance of the proposed control scheme. The robust friction state observer can successfully identify immeasurable friction state and the FNN estimator and adaptive approximation error estimator give the robustness to the proposed control scheme against the uncertainty of the friction parameters.

• 품질경영학회지
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• 제46권1호
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• pp.135-152
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• 2018

Purpose: This study attempted to analyze how the ego state of flight attendants affects their job satisfaction and customer orientation using Berne's (1966) transactional analysis and further compare the difference between job satisfaction and customer orientation depending on demographic characteristics, position, and ego state. Methods: The data was collected by using the structured questionnaires to flight attendant of major airline companies. The proposed research model is tested using 164 valid questionnaires using SPSS 23 and Smart PLS 2. Results: This research indicated the only free child ego sate among ego state factors of flight attendant was found to have a positive impact on job satisfaction. In the relationship between ego states and customer orientation, all ego state factors were found to have a significant influence on customer orientation. Conclusions: The study offered a theoretical and empirical foundation for future research by empirically identifying the relationship between ego state factors and customer orientation in the in-flight service and suggested the strategic implications to increase job satisfaction and customer orientation based on the psychology and ego state of flight attendant.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3128-3132
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• 2010

A disposable solid-state pH sensor was realized by utilizing two nanoporous Pt (npPt) electrodes and a copolyelectrolytic junction. One nanoporous Pt electrode was to measure the pH as an indicating electrode (pH-IE) and the other assembled with copolyelectrolytic junction was to maintain constant open circuit potential ($E_{oc}$) as a solid-state reference electrode (SSRE). The copolyelectrolytic junction was composed of cationic and anionic polymers immobilized by photo-polymerization of N,N'-methylenebisacrylamide, making buffered electrolytic environment on the SSRE. It was expected to make. The nanoporous Pt surrounded by a constant pH excellently worked as a solid state reference electrode so as to stabilize the system within 30 s and retain the electrochemical environment regardless of unknown sample solutions. Combination between the SSRE and the pH-IE commonly based on nanoporous Pt yielded a complete solid-state pH sensor that requires no internal filling solution. The solid state pH sensing chip is simple and easy to fabricate so that it could be practically used for disposable purposes. Moreover, the solid-state pH sensor successfully functions in calibration-free mode in a variety of buffers and surfactant samples.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2446-2448
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• 2009

• 여성건강간호학회지
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• 제23권4호
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• pp.287-298
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• 2017

Purpose: The purpose of this study was to deepen understanding the nature of the care experience by the mothers with adult children in persistent vegetative state. Methods: Participants were 7 mothers caring for their adult children in persistent vegetative state. Data were collected individually through in-depth interviews on their lived experiences. Also texts were included as data from literary works, novels, movies, essays, and arts containing on patients with persistent vegetative state and their mothers. Data were analyzed by van Manen's phenomenological methodology. Results: The essential themes of caring experiences of the mothers were as follows. The theme in relation to lived time has shown as back to the past and caring experience related lived body has emerged as locked the body in children. The theme related lived space was getting into the swamp and the theme in lived others was derived as lonely struggle into. Conclusion: The nature of mothers' caring experiences for adult children in persistent vegetative state is summarized as 'Do not off hand of hope in a locked state'. This study suggests long-term supports are necessary for mothers to care persistent vegetative state children.

• 천문학회보
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• 제37권2호
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• pp.115.1-115.1
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• 2012

The Ultraviolet Coronagraph Spectrometer on board the Solar and Heliospheric Observatory (SOHO) observes low ionization state coronal mass ejection plasma at ultraviolet wavelengths. The CME plasmas are often detected in O VI ($3{\times}10^5K$), C III ($8{\times}10^4K$), $Ly{\alpha}$, and $Ly{\beta}$. Earlier in situ observations by the Solar Wind Ion Composition Spectrometer (SWICS) on board Advanced Composition Explorer (ACE) have shown mostly high ionization state plasmas in interplanetary coronal mass ejections (ICME) events, which implies that most CME plasma is strongly heated during its expansion in solar corona. In this analysis, we investigate whether the low ionization state CME plasmas observed by UVCS occupy small enough fractions of the CME volume to be consistent with the small fraction of ICMEs measured by ACE that show low ionization plasma, or whether the CME must be further ionized after passing the UVCS slit. To do this, we determine the covering factors of low ionization state plasma for 10 CME events. We find that the low ionization state plasmas in CMEs observed by UVCS show small covering factors. This result shows that the high ionization state ICME plasmas observed by the ACE results from a small filling factor of cool plasma. We also find that the low ionization state plasma volumes in faster CMEs are smaller than in slower CMEs. Most slow CMEs in this analysis are associated with a prominence eruption, while the faster CMEs are associated with X-class flares.

• 전력전자학회논문지
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• 제7권1호
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• pp.11-17
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• 2002

디지털 회로 설계 방법의 하나인 Algorithmic State Machine (ASM)을 이용하여 반복운동을 하는 모터의 위치를 오차 없이 검출할 수 있는 방법에 대한 연구를 수행하였다. 이를 위하여 모터의 운동방향 변화 시 증분형 엔코더의 출력 패턴을 분석하고 이를 바탕으로 상태도 및 상태 테이블을 구성하였으며 모터의 운동방향 변화 시 정확하게 변화시점을 검출할 수 있는 디지털 회로를 설계하였다 설계된 회로의 유용성을 검증하기 위하여 시뮬레이션 및 실험을 수행하였다. 시뮬레이션 결과 모터의 운동 방향이 변화하는 모든 경우에 대해서 제안된 회로를 이용하면 오차 없이 모터의 위치를 검출할 수 있음을 입증하였다.

• Bulletin of the Korean Chemical Society
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• 제22권1호
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• pp.63-67
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• 2001

The photophysical properties and the singlet oxygen generation efficiency of tetrathiarubyrin have been investigated to elucidate the possibility of its use as a photodynamic therapy (PDT) photosensitizer by steady-state and time-resolved spectroscopic methods. The observed photophysical properties were affected by various molecular aspects, such as extended ${\pi}conjugation$, structural distortion, and internal heavy atom. The steady-state electronic absorption spectrum was red-shifted due to the extended $\pi-conjugation$, and the spin orbital coupling was enhanced by the structural distortion and the internal heavy atom effect. As a result of the enhanced spin orbital coupling, the triplet quantum yield increased to 0.90 $\pm$ 0.10 and the triplet state lifetime was shortened to 7.0 $\pm$ 1.2 ${\mu}s$. Since the triplet state decays at a relatively faster rate, the efficiency of the oxygen quenching of the triplet state decreases. The singlet oxygen quantum yield was estimated to be 0.52 $\pm$ 0.02, which is somewhat lower than expected. On the other hand, the efficiency of singlet oxygen generation during the oxygen quenching of triplet state, $f{\Delta}^T$, is near unity. Such high efficiency of singlet oxygen generation can be explained by the following two possible factors: The hydrogen bonding of ethanol which impedes the deactivation pathway of the charge transfer complex with oxygen to the ground state, the less probability of the aggregation formation.