• Title/Summary/Keyword: scale effect

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Effect of Chuna Treatment(Manipulation) on Cervical Sprain caused by Traffic Accident in Early Stage. - by Analysis of the Heart Rate Variability(HRV) and Visual Analogue Scale(VAS) - (경추 추나 치료가 교통사고 환자의 초기 HRV, VAS 변화에 미치는 영향)

  • Park, Ji-Hyun;Lee, Jung-Min;Hong, Seo-Young
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.4 no.2
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    • pp.47-60
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    • 2009
  • Objectives : The purpose of this study is to investigate the effect of chuna treatment on cervical sprain caused by traffic accident in early stage. Methods : This study carried out on 20 patients who have received hospital treatment in Daejeon Univ. cheonan Oriental Hospital. Non-chuna group got acupunture-therapy, herbal medication, physical therapy and Chuna group got chuna treatment besides. We measured Heart Rate Variability(HRV) and Visual Analog Scale(VAS) on 2nd, 4th day. Results : After being treated by our methods, Chuna Group showed the inclination to balance the sympathetic and parasympathetic nerve. In chuna group, an autonomic nerve activity showed the inclination to increase. But there were no significant difference between both groups. Chuna group's VAS were significantly decreased(p=0.043). Conclusions : The results suggest that Chuna treatment help traffic accident patients in early stage to reduce pain. Refer to autonomic nerve system, chuna treatment seem to do positive effect but Further long tenn study in a large scale is needed.

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A Study of Electronic Generation Technique for Dual Ultrasonic Transmitters for the Scale Prevention (스케일 방지를 위한 2쌍 초음파 발신기 구동기법 연구)

  • Heo, Pil-U;Lee, Yang-Rae;Im, Ui-Su
    • 연구논문집
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    • s.28
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    • pp.137-143
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    • 1998
  • In the case of a boiler, scale is made in the tube by the chemical reactions of Ca and Mg ions contained in the water, and heat transfer rate is reduced because of increasement of heat resistance in the pipe of the heat flow. Thus it brings to reduce the energy efficiency and to make environmental pollution by the use of chemicals for the prevention and removement of scale. In this paper, we discussed the design of electronic generator for dual ultrasonic transmitters and analyzed the effect of scale prevention by ultrasound.

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Monitoring of Chemical Processes Using Modified Scale Space Filtering and Functional-Link-Associative Neural Network (개선된 스케일 스페이스 필터링과 함수연결연상 신경망을 이용한 화학공정 감시)

  • Park, Jung-Hwan;Kim, Yoon-Sik;Chang, Tae-Suk;Yoon, En-Sup
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.12
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    • pp.1113-1119
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    • 2000
  • To operate a process plant safely and economically, process monitoring is very important. Process monitoring is the task to identify the state of the system from sensor data. Process monitoring includes data acquisition, regulatory control, data reconciliation, fault detection, etc. This research focuses on the data recon-ciliation using scale-space filtering and fault detection using functional-link associative neural networks. Scale-space filtering is a multi-resolution signal analysis method. Scale-space filtering can extract highest frequency factors(noise) effectively. But scale-space filtering has too large calculation costs and end effect problems. This research reduces the calculation cost of scale-space filtering by applying the minimum limit to the gaussian kernel. And the end-effect that occurs at the end of the signal of the scale-space filtering is overcome by using extrapolation related with the clustering change detection method. Nonlinear principal component analysis methods using neural network have been reviewed and the separately expanded functional-link associative neural network is proposed for chemical process monitoring. The separately expanded functional-link associative neural network has better learning capabilities, generalization abilities and short learning time than the exiting-neural networks. Separately expanded functional-link associative neural network can express a statistical model similar to real process by expanding the input data separately. Combining the proposed methods-modified scale-space filtering and fault detection method using the separately expanded functional-link associative neural network-a process monitoring system is proposed in this research. the usefulness of the proposed method is proven by its application a boiler water supply unit.

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Reinforcement Effect of Stabilizing Piles in Large-scale Cut Slops (대절토사면에 보강된 억지말뚝의 활동억지효과에 관한 연구)

  • 홍원표;한중근;송영석;신도순
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.06a
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    • pp.65-81
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    • 2003
  • During the last few decades in Korea, the development of hillside or mountain areas has rapidly increased for infrastructure construction such as railroads, highways and housing. Many landslides have occurred during these constructions. Also, the amount and scale of damage caused by landslides have increased every year. In the case of Far East Asia including Korea, the damage of landslides is consequently reported during the wet season. In this paper, the effect of stabilizing piles on slope stability is checked and the behavior of slope soil and piles are observed throughout the year by field measurements in the large-scale cut slopes. In particular a large-scale cut slope situated on the construction site for the express highway in Donghae, Korea. First of all, The behavior of the slope soil was measured by inclinometers during slope modification. Landslides occurred in this area due to the soil cutting for slope modification. The horizontal deformations of slope soil gradually increased and rapidly decreased at depth of sliding surface indicating that the depth of sliding surface below the ground surface can be predicted. On the basis of being able to predict the depth of the sliding surface, stabilizing piles were designed and constructed in this slope. To ensure the stability of the reinforced slope using stabilizing piles, an instrumentation system was installed. The maximum deflection of piles is measured at the pile head and it is noted that the piles deform like deflection on a cantilever beam. The maximum bending stress of piles is measured at the soil layer. The pile above the soil layer is subjected to lateral earth pressure due to driving force of the slope, while pile below soil layer is subjected to subgrade reaction against pile deflection. As a result of research, the effect and applicability of stabilizing piles in large-scale cut slopes could be confirmed sufficiently.

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A Study on the Similitude of member Behavior for Small-Scale Modeling of Reinforced Concrete Structure (철근콘크리트 축소모델의 부재거동 상사성에 관한 연구)

  • 이한선;장진혁
    • Magazine of the Korea Concrete Institute
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    • v.8 no.3
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    • pp.177-185
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    • 1996
  • Four types of experiments were performed to check the similitude of member behavior between prototype and 1 /10 scale models : (1) Test of slender columns with P-$\Delta$ effect, (2) Test of short columns with and without confinement steel, (3) Test of simple beams without stirrups, and (4) 'T-beam test. Based on the results of experiments, the conclusions were made as follows : (1) The P-$\Delta$ effect of slender columns can be almost exactly represented by 1/10 scale model. (2) The effect of confinement on short columns by the hoop steel can be also roughly simulated by 1/10 scale model. (3) The failure modes of simple beams without stirrups are brittle shear failures in prototype whereas those of 1/10 scale models are the ductile yielding of tension steel followed by large diagonal tension cracking and compressive concrete failure. (4) The behaviors of prototype and 1/10 scale model in T-beams appear very similar.

The Anti-scale Effect according to Array of Magnetic Device (자화장치의 배열별 스케일 생성 억제 효과)

  • Nam, Joongwoo;Han, Yunsu;Lee, Jonghwi;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.2
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    • pp.13-17
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    • 2013
  • Clogging phenomenon in drainage system is one of the important problems and this phenomenon would be bad effect to structure of tunnel, so it needs a remedy urgently. Recently, scale in drainage pipe is removed by water jet cleaning and other treatment. But these treatments need much cost and regular management. In this study, magnetic device was used to solve this problem and an effect of prohibiting scale in accordance with array of magnetic device was investigated. Analysis method was visual analysis and measuring weight of each pipes. As a result, interior top and out-bottom (CASE II) was the most effective array to prohibit scale. and interior left and right (CASE III), interior top and bottom (CASE I) was effective for prohibiting scale in order.

Effective mechanical properties of micro/nano-scale porous materials considering surface effects

  • Jeong, Joonho;Cho, Maenghyo;Choi, Jinbok
    • Interaction and multiscale mechanics
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    • v.4 no.2
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    • pp.107-122
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    • 2011
  • Mechanical behavior in nano-sized structures differs from those in macro sized structures due to surface effect. As the ratio of surface to volume increases, surface effect is not negligible and causes size-dependent mechanical behavior. In order to identify this size effect, atomistic simulations are required; however, it has many limitations because too much computational resource and time are needed. To overcome the restrictions of the atomistic simulations and graft the well-established continuum theories, the continuum model considering surface effect, which is based on the bridging technique between atomistic and continuum simulations, is introduced. Because it reflects the size effect, it is possible to carry out a variety of analysis which is intractable in the atomistic simulations. As a part of the application examples, the homogenization method is applied to micro/nano thin films with porosity and the homogenized elastic coefficients of the nano scale thickness porous films are computed in this paper.

Size dependent effect on deflection and buckling analyses of porous nanocomposite plate based on nonlocal strain gradient theory

  • Khazaei, Pegah;Mohammadimehr, Mehdi
    • Structural Engineering and Mechanics
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    • v.76 no.1
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    • pp.27-56
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    • 2020
  • In this paper, the deflection and buckling analyses of porous nano-composite piezoelectric plate reinforced by carbon nanotube (CNT) are studied. The equations of equilibrium using energy method are derived from principle of minimum total potential energy. In the research, the non-local strain gradient theory is employed to consider size dependent effect for porous nanocomposite piezoelectric plate. The effects of material length scale parameter, Eringen's nonlocal parameter, porosity coefficient and aspect ratio on the deflection and critical buckling load are investigated. The results indicate that the effect of porosity coefficient on the increase of the deflection and critical buckling load is greatly higher than the other parameters effect, and size effect including nonlocal parameter and the material length scale parameter have a lower effect on the deflection increase with respect to the porosity coefficient, respectively and vice versa for critical buckling load. Porous nanocomposites are used in various engineering fields such as aerospace, medical industries and water refinery.

Estimation of Modification Factor for Scale Effect of the Front of Flood Wave Propagation (홍수파 선단의 축척효과에 대한 보정계수 산정)

  • Jeong, Seok-il;Kim, Soo young;Lee, Seung Oh
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.6
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    • pp.39-44
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    • 2016
  • Recently, there has been increasing concern regarding the collapse of hydraulic structures due to abnormal climate conditions. Therefore, numerous studies of the collapse of hydraulic structures have been carried out. In particular, the velocity of the propagation of a flood wave-front is important for predicting the inundation safety and establishing an EAP (Emergency Action Plan). Although many hydraulic tests have been conducted for precise predictions of a flood wave-front, the scale effect from downsizing has not considered. In this study, the relationships between surface tension and the concentration of surfactant, between surface tension and the velocity of flood wave propagation, and between surface tension and the Weber Number were derived through hydraulic tests using a surfactant and image analysis equipment. Based on these relations, the modification factor for the scale effect of the front of flood wave propagation was suggested. The results highlight the necessity of a modification factor when the Weber Number is lower than 12.2, but the scale effect can be ignored when the Weber Number over 12.2.