• Title/Summary/Keyword: Dynamic Area

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Nonlinear dynamic properties of dynamic shear modulus ratio and damping ratio of clay in the starting area of Xiong'an New Area

  • Song Dongsong;Liu Hongshuai
    • Earthquakes and Structures
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    • v.26 no.2
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    • pp.97-115
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    • 2024
  • In this paper, a database consisting of the dynamic shear modulus ratio and damping ratio test data of clay obtained from 406 groups of triaxial tests is constructed with the starting area of Xiong'an New Area as the research background. The aim is to study the nonlinear dynamic properties of clay in this area under cyclic loading. The study found that the effective confining pressure and plasticity index have certain influences on the dynamic shear modulus ratio and damping ratio of clay in this area. Through data analysis, it was found that there was a certain correlation between effective confining pressure and plasticity index and dynamic shear modulus ratio and damping ratio, with fitting degree values greater than 0.1263 for both. However, other physical indices such as the void ratio, natural density, water content and specific gravity have only a small effect on the dynamic shear modulus ratio and the damping ratio, with fitting degree values of less than 0.1 for all of them. This indicates that it is important to consider the influence of effective confining pressure and plasticity index when studying the nonlinear dynamic properties of clays in this area. Based on the above, prediction models for the dynamic shear modulus ratio and damping ratio in this area were constructed separately. The results showed that the model that considered the combined effect of effective confining pressure and plasticity index performed best. The predicted dynamic shear modulus ratio and damping ratio closely matched the actual curves, with approximately 88% of the data falling within ±1.3 times the measured dynamic shear modulus ratio and approximately 85.1% of the data falling within ±1.3 times the measured damping ratio. In contrast, the prediction models that considered only a single influence deviated from the actual values, particularly the model that considered only the plasticity index, which predicted the dynamic shear modulus ratio and the damping ratio within a small distribution range close to the average of the test values. When compared with existing prediction models, it was found that the predicted dynamic shear modulus ratio in this paper was slightly higher, which was due to the overall hardness of the clay in this area, leading to a slightly higher determination of the dynamic shear modulus ratio by the prediction model. Finally, for the dynamic shear modulus ratio and damping ratio of the engineering site in the starting area of Xiong'an New Area, we confirm that the prediction formulas established in this paper have high reliability and provide the applicable range of the prediction model.

Experimental and Analysis Study on Transition Area Between Bridge and Earthwork (교량, 토공 접속구간 궤도동적계측 및 해석에 관한 연구)

  • 강윤석;나성훈;신정렬;양신추
    • Proceedings of the KSR Conference
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    • 2002.05a
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    • pp.250-255
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    • 2002
  • The transition between bridge and earthwork often causes the problems of maintenance. The damages of the track on the transition area influence running safety of train and serviceability, increase the maintenance cost. Therefore it is very important to evaluate the dynamic responses of transition and take a efficient measure. In order to evaluate the dynamic behavior of track, the field estimations are performed at the transition area of a conventional line between bridge and earthwork. And the track system on the transition area numerically analyzed to evaluate the dynamic behavior of damaged track with void sleeper. The measured values and Analysis results such as wheel contact force, rail stress, displacement acceleration and track irregularity in the transition area show the dynamic forces are severe. So it is recommended that the transition area should be improved the rigidity by reinforcing the rail.

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Emotion Evaluation algorithm of Brain Information System using Dynamic Genitive Maps (동적인지 맵을 이용한 뇌 정보 처리 시스템의 감정 평가 알고리즘)

  • 홍인택;김성주;서재용;김용택;전홍태
    • Proceedings of the IEEK Conference
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    • 2003.07d
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    • pp.1243-1246
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    • 2003
  • It is known that structure of Human's brain information system is controlled by cerebral cortex mainly. Cerebral cortex is divided by sensory area, motor area and associated area largely. Sensory area takes part in information from environment and motor area is actuation by decision as associated area determined. It is possible to copy brain information system by input-output pattern. but there is difficulty in modeling of memorizing new information. Such action is performed by Limbic Lobe and Papez circuit which is controlled by intrinsic emotion. So we need of definition of emotion's role in decision. In this paper, we define roles of emotion in intrinsic decision using Dynamic Cognitive Maps(DCMs). The emotion is evaluated by outside information then intrinsic decision performed as how much emotion variated. The dynamic cognitive maps take part in emotion evaluating process.

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The Comparision of the Static Balance, Contact Area, and Plantar Pressure of Flexible Flat Foot According to Elastic Taping

  • Hyeon-Seong Joo;Sam-Ho Park;Myung-Mo Lee
    • Physical Therapy Rehabilitation Science
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    • v.11 no.4
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    • pp.421-429
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    • 2022
  • Objective: The purpose of this study was to compare and analyze the effects of arch support taping on static balance, static/dynamic foot contact area, and ground reaction force during walking according to the types of elastic tapes with mechanical elasticity differences. Design: Cross-sectional study Methods: Twenty-six participants selected for flexible flat feet through the navicular drop test were randomly assigned to non-taping, Dynamic-taping, and Mechano-taping conditions. Static balance and foot contact area were compared in the standing posture according to arch support taping conditions, and foot contact area and ground reaction force were compared during walking. Results: There was no significant difference in static balance according to the taping condition in the standing position, but the foot contact area in the Mechano-taping condition showed a significant decrease compared to the non-taping condition (p<0.05). The foot contact area during walking significantly decreased in the Dynamic-taping and Mechano-taping conditions (p<0.05), but there was no significant difference between the ground reaction force. Conclusions: Based on the results of this study, it was confirmed that among the types of elastic taping, arch support taping using dynamic taping and Mechano-taping has the effect of supporting the arch with high elastic recovery. Any type of elastic tape can be used for arch alignment in flexible flat foot.

Compressed Sensing Based Dynamic MR Imaging: A Short Survey (Compressed Sensing 기법을 이용한 Dynamic MR Imaging)

  • Jung, Hong;Ye, Jong-Chul
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.5
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    • pp.25-31
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    • 2009
  • The recently developed sampling theory, "compressed sensing" is gathering huge interest in MR reconstruction area because of its feasibility of high spatio-temporal resolution of dynamic MRI which has been limited in conventional methods based on Nyquist sampling theory. Since dynamic MRI usually has high redundant information along temporal direction, this can be very sparsely represented in most of cases. Therefore, compressed sensing that exploits the sparsity of unknown images can be effectively applied in most of dynamic MRI. This review article briefly introduces currently proposed compressed sensing based dynamic MR imaging algorithms and other methods exploiting sparsity. By comparing them with conventional methods, you may have insight how the compressed sensing based methods can impact nearly every area of clinical dynamic MRI.

Surface Saturation Area-Subsurface Outflow-Soil Moisture Storage Relationships: II. Dynamic Analysis (지표포화지역-중간류유출-흙수분저류량 관계: II. 동적 분석)

  • 이도훈;이은태
    • Water for future
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    • v.29 no.2
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    • pp.143-151
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    • 1996
  • The dynamic responses in the subsurface outflow, surface saturation area, soil moisture storage are established by numerical experiments with Richards equation. In addition to this, the dynamical relationship between surface saturation area and subsurface outflow, and between surface saturation area and soil moisture storage are also determined by varying the hillslope shape, soil type, and boundary condition. The simulation results indicate that the dynamical relationships between surface saturation area and subsurface outflow, and between surface saturation area and soil moisture storage are approximated by the steadystate relationships. And the dynamic responses of subsurface outflow and surface saturation area are characterized by the double peaks although the rainfall pattern is asimple pulse input. As a result of numerical simulation, the physical mechanism for the occurrence of the double peaks is explained using the concept of variable source area.

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Spatial Structure and Dynamic Evolution of Urban Cooperative Innovation Network in Guangdong-Hong Kong-Macao Greater Bay Area, China: An Analysis Based on Cooperative Invention Patents

  • HU, Shan Shan;KIM, Hyung-Ho
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.9
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    • pp.113-119
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    • 2021
  • With the increasing pressure of international competition, urban agglomeration cooperation and innovation had become an important means of regional economic development. This study analyzed the spatial characteristics of the Urban Cooperative Innovation Network in Guangdong-Hong Kong-Macao Greater Bay Area, found out the dynamic evolution law of innovation, provided suggestions for policy management departments, and effectively planned the industrial layout. According to the data of the State Intellectual Property Office of China, this study researched invention patents from 2005 to 2019. This paper constructed the urban cooperative innovation network, and took 11 cities in the bay area as the research objects, and used social network analysis to study the spatial structure and dynamic evolution of the urban innovation network. Every indicator reflected the urban cooperative innovation, but they all showed a certain decline in 2008-2010. And it is inferred that the innovation network space of each city will be "obvious fist advantages, significant spillover effect and weakening role of Hong Kong and Macao". This paper divided urban cooperative innovation of Guangdong-Hong Kong-Macao Greater Bay Area into three stages. Summing up the characteristics of each stage is helpful to recognize the changes of urban cooperative innovation and to do a good job in industrial layout planning.

MOBA based design of FOPID-SSSC for load frequency control of interconnected multi-area power systems

  • Falehi, Ali Darvish
    • Smart Structures and Systems
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    • v.22 no.1
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    • pp.81-94
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    • 2018
  • Automatic Generation Control (AGC) has functionally controlled the interchange power flow in order to suppress the dynamic oscillations of frequency and tie-line power deviations as a perturbation occurs in the interconnected multi-area power system. Furthermore, Flexible AC Transmission Systems (FACTS) can effectively assist AGC to more enhance the dynamic stability of power system. So, Static Synchronous Series Compensator (SSSC), one of the well-known FACTS devices, is here applied to accurately control and regulate the load frequency of multi-area multi-source interconnected power system. The research and efforts made in this regard have caused to introduce the Fractional Order Proportional Integral Derivative (FOPID) based SSSC, to alleviate both the most significant issues in multi-area interconnected power systems i.e., frequency and tie-line power deviations. Due to multi-objective nature of aforementioned problem, suppression of the frequency and tie-line power deviations is formularized in the form of a multi-object problem. Considering the high performance of Multi Objective Bees Algorithm (MOBA) in solution of the non-linear objectives, it has been utilized to appropriately unravel the optimization problem. To verify and validate the dynamic performance of self-defined FOPID-SSSC, it has been thoroughly evaluated in three different multi-area interconnected power systems. Meanwhile, the dynamic performance of FOPID-SSSC has been accurately compared with a conventional controller based SSSC while the power systems are affected by different Step Load Perturbations (SLPs). Eventually, the simulation results of all three power systems have transparently demonstrated the dynamic performance of FOPID-SSSC to significantly suppress the frequency and tie-line power deviations as compared to conventional controller based SSSC.

Comparison Between the Dynamic Properties and Noise Isolation Performances for a Floor Impact Isolation Pad (바닥충격음 완충재의 동적특성과 소음저감 성능 비교)

  • Yang, Soo-Young;Lee, Dong-Hoon;Hong, Boung-Kuk;Song, Hwa-Young;Lee, Joo-Wone
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.275-278
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    • 2005
  • In this study, the dynamic properties of a floor impact sound isolation pad expressed in terms of the natural frequency, the dynamic stiffness per unit area and the loss factor are measured by the resonant method. By using the measured dynamic properties, the vibration transmissibility diagram is obtained for each isolation pad, which is compared with the values tested by the impact sound sources at the room in an apartment. From the comparative results, it is found that the noise reduction Performances. of isolation pads are closely connected with the natural frequency and the dynamic stiffness per unit area.

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Case Studies of Several Load Tests for Large Diameter Battered Steel Pipe Piles Constructed on the Offshore Area. (대구경 해상 강관말뚝의 설계지지력 확인을 위한 여러 가지 재하시험의 적용)

  • 이정학;서덕동;정헌주
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.291-298
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    • 2001
  • It is very difficult to accomplish load tests of piles with large diameter constructed on the offshore area, because of requirement for large scaled loading equipment and bad testing conditions. Therefore, so far in many cases pile driving dynamic formulas have applied to quality control, and recently dynamic load test method is widely used for confirming bearing capacities of such piles. However, in cases of piles with very large diameter about 2,500mm, it is nearly impossible for regular type load test methods of piles such as static and dynamic to apply owing to very large design load. This is case studies of load tests such as modified static and dynamic load tests of piles and point load tests of rock samples for estimating rational allowable bearing capacity of very large diameter piles constructed on the marine area.

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