• Structural Engineering and Mechanics
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• 제84권5호
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• pp.699-706
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• 2022

Settlement control techniques are critical for the safety of shield tunnel constructions, especially for facing complex situations. In this study, the shield tunnel structure from Huaita east road station to Heping Road station in Xuzhou metro No.3 line (China) is taken as engineering background, which has various complex problems of the upper-soft and lower-hard composite stratum conditions, twin curve shield tunnels, and underpass the foundation of the piled raft. The deformation characteristics of shield tunnelling passing through buildings are explored. Subsequently, comprehensive research methods of numerical simulation and field measurement are adopted to analyzing the effectiveness of settlement control by using the top grouting technique. The results show that the settlement of the buildings has obvious spatial characteristics, and the hysteresis effect can be obviously observed in soil deformation caused by shield construction. Meanwhile, the two shield constructions can cause repeated disturbances, reducing the soil deformation's hysteresis effect. Moreover, the shield tunnel's differential settlement is too large when a single line passes through, and the shield construction of the outer curve can cause more significant disturbance in the tunnel than the inside curve. Notably, the proposed process control parameters and secondary topgrouting method can effectively control the deformation of the shield tunnel, especially for the long-term deformation.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.850-860
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• 2023

An industrial control process multiple-input multiple-output (MIMO) coupled system is analyzed in this study as an example of a Loss of Coolant Accident (LOCA) simulation system. Ordinary control algorithms can complete the steady state of the control system and even reduce the response time to some extent, but the entire system still consumes a large amount of energy after reaching the steady state. So a multivariable decoupled energy-saving control method is proposed, and a novel energy-saving function (economic function, Eco-Function) is specially designed based on the active disturbance rejection control algorithm. Simulations and LOCA simulation system tests show that the Eco-function algorithm can cope with the uncertainty of the multivariable system's internal parameters and external disturbances, and it can save up to 67% of energy consumption in maintaining the parameter steady state.

• Current Optics and Photonics
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• 제7권5호
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• pp.529-536
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• 2023

The Morlet wavelet transform method is proposed to analyze a single interferogram with spatial carrier frequency that is captured by an optical interferometer. The method can retain low frequency components that contain the phase information of a measured optical surface, and remove high frequency disturbances by wavelet decomposition and reconstruction. The key to retrieving the phases from the low-frequency wavelet components is to extract wavelet ridges by calculating the maximum value of the wavelet transform amplitude. Afterwards, the wrapped phases can be accurately solved by multiple iterative calculations on wavelet ridges. Finally, we can reconstruct the wave-front of the measured optical element by applying two-dimensional discrete cosine transform to those wrapped phases. Morlet wavelet transform does not need to remove the spatial carrier frequency components manually in the processing of interferogram analysis, but the step is necessary in the Fourier transform algorithm. So, the Morlet wavelet simplifies the process of the analysis of interference fringe patterns compared to Fourier transform. Consequently, wavelet transform is more suitable for automated programming analysis of interference fringes and avoiding the introduction of additional errors compared with Fourier transform.

• International Journal of Computer Science & Network Security
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• 제24권2호
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• pp.169-177
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• 2024

Interacting Spherical tank has maximum storage capacity is broadly utilized in industries because of its high storage capacity. This two tank level system has the nonlinear characteristics due to its varying surface area of cross section of tank. The challenging tasks in industries is to manage the flow rate of liquid. This proposed work plays a major role in controlling the liquid level in avoidance of time delay and error. Several researchers studied and investigated about reducing the nonlinearity problem and their approaches do not provide better result. Different types of controllers with various techniques are implemented by the proposed system. Intelligent Adaptive Neuro Fuzzy Inference System (ANFIS) based Sliding Mode Controller (SMC) with Fractional order PID controller is a novel technique which is developed for a liquid level control in a interacting spherical tank system to avoid the external disturbances perform better result in terms of rise time, settling time and overshoot reduction. The performance of the proposed system is obtained by analyzing the simulation result obtained from the controller. The simulation results are obtained with the help of FOMCON toolbox with MATLAB 2018. Finally, the performance of the conventional controller (FOPID, PID-SMC) and proposed ANFIS based SMC-FOPID controllers are compared and analyzed the performance indices.

• 대한조선학회논문집
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• 제61권4호
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• pp.216-225
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• 2024

The sliding mode controller has characteristics that ensure stability and robustness against system uncertainty and disturbance. However, chattering occurs in the control inputs to compensate for system uncertainties and ensure that the system operates efficiently on the sliding surface. When the disturbance is large, using a sliding mode controller requires a large control gain value, which also increases chattering and reduces performance. Therefore, in this study, a nonlinear disturbance observer was used to compensate for external disturbances such as currents and waves and uncertainty in the control system for autonomous underwater vehicles. Accordingly, a robust controller can be implemented while reducing the control gain. The disturbance observer serves to ensure that the behavior of the actual system is closer to the nominal model by compensating for uncertainties between the actual system model and the nominal model during the control process. Therefore, the simulation results show that the performance and robustness of the autonomous underwater vehicle controller are improved by introducing a disturbance observer.

• Journal of Ginseng Research
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• 제48권5호
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• pp.449-453
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• 2024

Korean Red Ginseng (KRG) has long been used not only as a food supplement but also as a treatment for various diseases. Ginseng originated in South Korea, which later spread to China and Japan, has a wide range of pharmacological activities including immune, endocrine, cardiovascular, and central nervous system effects. KRG is produced by repetitions of steaming and drying of ginseng to extend preservation. During this steaming process, the components of ginseng undergo physio-chemical changes forming a variety of potential active constituents including ginsenoside-Rg3, a unique compound in KRG. Pandemic Coronavirus disease 2019 (COVID-19), has affected both men and women differentially. In particular, women were more vulnerable to COVID-related distress which in turn could aggravate menopause-related disturbances. Complementary and alternative medicinal plants could have aided middle-aged women for several menopause-related symptoms during and post COVID-19 pandemic. This review aimed to explore the beneficial effects of KRG on menopausal symptoms and gynecological cancer.

• 한국조경학회지
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• 제37권6호
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• pp.96-105
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• 2010

본 연구는 하천 경관요소 중에서 비교적 단시간에 걸쳐 변화하는 사주 지형과 식생 분포의 역동적 형성과정을 밝히기 위해 수행되었으며, 연구 대상 하천은 2002년 이후 생태계보전지역으로 관리되고 있는 탄천 하류부 구간이다. 이를 위해서 사주지형의 변화는 항공사진과 경관사진을 통해 그 형성과정을 파악하고 현재 사주 지형 위에 형성된 식생의 분포를 현장조사를 통해 분석하였다. 분석한 연구 결과는 다음과 같다. 첫째, 1980년대 후반에 직강화 되었던 하도 내에서 1990년대에 들어 사주의 발달이 현저하여 다양한 형태의 사주가 형성되었고 이는 지속적으로 변화하였다. 초기에 사주가 형성되고 시간이 경과함에 따라, 하도 내 흐름 특성에 따라 사주의 면적과 높이가 변하였다. 둘째, 식생의 분포에 있어서는 물과 접촉 빈도가 높은 하안부는 교란의 정도가 심하기 때문에 무식생 상태이거나, 간헐적인 식생이 분포하여 피도가 낮게 나타났으며, 고수부지 쪽으로 형성된 사주에는 목본류나 정수식물군락이 활착되면서 식생 피도가 높게 나타나 안정식생역을 형성하였다. 셋째, 사주와 식생형성과정의 관계는 사주의 형태와 식생의 안정성 여부에 따라 저수로변 사주, 불안정 식생 저수로변사주, 안정식생 하중주 그리고 불안정식생 하중주 4가지 유형으로 나타났다. 본 연구를 통해 밝힌 하도 내 사주와 하천식생의 형성과정에 있어서의 상호관계는 모래하상의 하천부지에서 식물종이나 식재위치 선정에 유용할 것이나, 하천생태계 복원을 위한 실행사업의 식재 지침으로 활용되기 위해서는 다양한 특성을 지닌 하천에 대한 보다 폭 넓은 사례연구가 뒷받침되어야 할 것이다.

• 한국안전학회지
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• 제35권1호
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• pp.116-129
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• 2020

Resilience is defined as the intrinsic ability of a system to adjust its functioning prior to, during, or following changes and disturbances, so that it can sustain required operations or functions with the related systems under both expected and unexpected conditions. Resilience engineering is a relatively new paradigm for safety management that focuses on how to cope with complexity under pressure or disturbance to achieve successful functioning. This study aims to develop a quantitative resilience model for severe accident response organizations of nuclear power plants using the Analytic Hierarchy Process (AHP) method. First, we investigated severe accident response organizations based on a radiation emergency plan in the Korean case and developed a qualitative resilience model for the organizations with resilience-influencing factors, which have been identified in the author's previous studies. Then, a quantitative model for entire severe accident response organizations was developed by using the Analytic Hierarchy Process (AHP) method with a tool for System Dynamics. For applying the AHP method, several experts who are working on implementing, regulating or researching the severe accident response participated in collecting their expertise on the relative importance between all the possible relations in the model. Finally, a sensitivity analysis was carried out to discuss which factors have the most influenceable on resilience.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제11권1호
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• pp.287-296
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• 1989

하악골 과두돌기 골절은 하악골에 있어서 자주 일어나는 골절중의 하나이며, 이 부위는 해부학적 구조로 이상적인 Reposition ( )이 통례적으로 불가능 하다고 할 수 있을 정도로 어렵기 때문에 치료방법이 선택적으로 이용된다. 수술후 충분한 악관절기능을 발휘하는데 문제가 있을수도 있기 때문에 (Arthropathia deformans) 치료 계획을 세우는데 있어서는 우선 관절기능이 정상적으로 회복되어져야 하며, 또한 악관절 강직에 따른 안면골의 발육 부전으로 인한 악골기형을 고려하여야 한다는데 치료의 촛점이 두어져야 한다. 본인은 1981년 부터 1987년까지 인제대학부속부산백병원에서 치료한 바 있는 73명을 대상으로 (88골절선) 임상조사와 문헌적 고찰을 통하여 악관절 과두돌기 골절에 대한 치료방법의 선택기준 및 합병증 방지에 그 일익을 하고자 이 연구를 시행하였다.

• 인지과학
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• 제6권1호
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• pp.47-71
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• 1995

글자의 이중상으로 인한 심리적 혼란감을 '글자멀미'라 정의하였고,눈운동 및 글자 인식 과정이 교란될 때 글자 멀미가 발생한다는 가설을 검증하기 위하여 자극의 노출시간과 글자의 친숙도가 글자 멀미에 미치는 효과를 측정하였다.글자 멀미는 자극 노출 시간이 50ms,100ms,3000ms로 길어짐에 따라,덜 친숙한 외국 문자보다는 친숙한 한글에서 유의미한 단어보다는 무의미한 단어에서 큰것으로 나타났다.이러한 실험발견은 이중상을 제거하려는 눈 운동이 실효를 거두지 못함에 따라 글자 멀미가 발생한다는 것,친숙한 글자일수록 글자 인식 과정의 개입을 더 강화하며 그결과 이중상에 의한 교란 효과가 증폭된다는것,글자 형태는 친숙하지만 의미추출이 어렵게 되면 이중상의 교란효과가 가중된다는 것을 암시한다.의미를 처리하는 경향이 클수록 이중상에 의한 글자 멀미가 심해진다는 가설을 좀 더 분명히 검증하기 위하여 여섯 개의 점으로 구성된 점자를 시각적으로 인식하도록 피험자들을 학습시킨 결과,학습율이 증가함에 따라 글자 멀미가 증가하는 것으로 나타나, 하나의 자극을 의미있는 상징으로 취급하여 해석하려 할때 글자멀미가 증가한다는 결론을 얻었다.