• Title/Summary/Keyword: Increment

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A STREE-STRAIN THEORY FOR COMPACTED ROCKFILL (다짐된 사약재료의 응력-변형 이론)

  • 이영희
    • Geotechnical Engineering
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    • v.3 no.1
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    • pp.77-96
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    • 1987
  • Based on observation emerged from the undrained tests and the anisotropic consolidation tests, an incremental stress-strain theory for rockfill is proposed in a manner similar to that developed ky Cambridge Group for normally consolidated soils; the volumetric strain due to stress increment is the same as the increment due to an undrained component followed by an increment along the constant stress ratio path. The strains in drained tests are predicted from those in the undrained tests and in the anisotropic consolidation tests. An expression for the undrained stress path is derived based on the bilinear relationship between the pore pressure developed and the stress ratio observed during untrained tests. Good agreement is found between the calculated and measured strains. This trend in behaviour would be helpful in establishing a stress.strain model for rockfill using the elasto-plastic behaviour with the concept of plastic potentials and flow rules.

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Back Analysis of Earth Retaining Wall Using Increment of Sequential Displacement (변위증분을 이용한 흙막이 벽의 역해석에 관한 연구)

  • 장범수;이승훈;김종민;김수일
    • Journal of the Korean Geotechnical Society
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    • v.19 no.5
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    • pp.7-14
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    • 2003
  • In the back analysis of braced excavation based on displacement measurements, the accumulated errors of abnormal displacement caused by unexpected loads are usually observed. To minimize such errors, in this study, displacement increment was used fur back analysis rather than displacement for the conventional method. That is, the increment of sequential displacement is used as the objective function and the back analysis program is developed by taking advantage of sequential linear programming method by modified method of feasible directions. Based on small scale model test, the analysis of proposed method is verified.

Study for Increment Method of ATC (Available Transfer Capability) (가용 송전 능력(Available Transfer Capability : ATC)의 증대 방안에 대한 연구)

  • Lee, Y.H.;Baek, Y.S.;Song, K.B.;Chu, J.B.;Won, J.R.
    • Proceedings of the KIEE Conference
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    • 2001.05a
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    • pp.55-57
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    • 2001
  • In this paper, algorithm for increment of ATC is proposed. ATC of the power transfer system is determined by the smallest ATC among transmission lines' in the power transfer system. So power flow of that transmission line shall be decreased to increase ATC, using the redistribution of each generation power with liner programing method. By the studying example case, $10\sim20%$ increment of ATC is confirmed in the power transfer system.

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Development of Static-explicit rigid-plastic finite Element Method and investigate the effect of punch stroke and the strain increment in Osakada method (정적-외연적 강소성 유한요소법의 개발 및 펀치 행정구간에 따른 영향과 Osakada 방법의 초기 변형율 증분에 따른 영향분석)

  • 정동원;이승훈
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1545-1548
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    • 2003
  • In rigid-plastic finite element method, there is a heavy computation time and convergence problem. In this study. static-explicit rigid-plastic finite element method will be introduced. This method is the way that restrict the convergence interval. In result, convergence problem and computation time due to large non-linearity in the existing numerical analysis method were no longer a critical problem. Also, we investigated the effect of punch stroke and the strain increment this method. It is expected that various results from the numerical analysis will give very useful information for the design of tools in sheet metal forming process.

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Quality Characteristics of Yaksik Prepared by Different Methods (제조방법에 따른 약식의 품질 특성)

  • 김종군;김주숙
    • Korean journal of food and cookery science
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    • v.16 no.5
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    • pp.453-459
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    • 2000
  • Quality characteristics of Yaksik prepared with glutinuous rice soaked for different time lengths were investigated. Moisture contents increased with the increment of soaking time. In Hunter's color value, the lightness decreased and redness and yellowness increased by the increment of soaking time. Samples prepared with a commercial formula showed increased red and yellow colors due to the addition of caramel sauce. The firmness decreased with the increment of soaking time during storage. However, the samples prepared with 2 hr-soaking were retrograded rapidly. In peroxide value, there were no differences among samples. In microbiological evaluation, samples prepared with a commercial formula had prolonged shelf lives probably due to the preservatives contained. Samples prepared with 6 hr-soaking showed the highest score in sensory evaluation.

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Computer simulation for dynamic wheel loads of heavy vehicles

  • Kawatani, Mitsuo;Kim, Chul-Woo
    • Structural Engineering and Mechanics
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    • v.12 no.4
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    • pp.409-428
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    • 2001
  • The characteristics of dynamic wheel loads of heavy vehicles running on bridge and rigid surface are investigated by using three-dimensional analytical model. The simulated dynamic wheel loads of vehicles are compared with the experimental results carried out by Road-Vehicles Research Institute of Netherlands Organization for Applied Scientific Research (TNO) to verify the validity of the analytical model. Also another comparison of the analytical result with the experimental one for Umeda Entrance Bridge of Hanshin Expressway in Osaka, Japan, is presented in this study. The agreement between the analytical and experimental results is satisfactory and encouraging the use of the analytical model in practice. Parametric study shows that the dynamic increment factor (DIF) of the bridge and RMS values of dynamic wheel loads are fluctuated according to vehicle speeds and vehicle types as well as roadway roughness conditions. Moreover, there exist strong dominant frequency resemblance between bounce motion of vehicle and bridge response as well as those relations between RMS values of dynamic wheel loads and dynamic increment factor (DIF) of bridges.

A Study on the Productivity Increment through Construction of Lean Production System for Automobile Plant in China (중국 자동차 공장의 린 생산 체계 구축을 통한 생산성 향상에 관한 연구)

  • Jang, Jung-Hwan;Zhang, Jing-Lun;Yoo, Sung-Hee;Lee, Chang-Ho
    • Journal of the Korea Safety Management & Science
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    • v.14 no.1
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    • pp.117-122
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    • 2012
  • This paper deals with the productivity increment through construction of lean production system for automobile factory in China. This lean production system has been progressed according to 5 steps. Step 1 is the work preparation. Step 2 is the process design. Step 3 is the establishment of method to count production quantity. Step 4 is the establishment of measuring method for input and output. Finally, step 5 is the construction of flexible production system able to adapt for environment change. This lean production system is expected to obtain the productivity increment by 50% for plastic plant and reduction by 50% in inventory quantity.

A load increment method for ductile reinforced concrete (RC) frame structures considering strain hardening effects

  • Gunhan Aksoylu, M.;Girgin, Konuralp
    • Structural Engineering and Mechanics
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    • v.38 no.2
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    • pp.231-247
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    • 2011
  • This study introduces a new load increment method for the ductile reinforced concrete (RC) frame structures by including strain-hardening effects. The proposed method is a nonlinear static analysis technique employed for RC frame structures subjected to constant gravity loads and monotonically increasing lateral loads. The material nonlinearity in RC structural elements is considered by adopting plastic hinge concept which is extended by including the strain hardening as well as interaction between bending moment and axial force. Geometric non-linearity, known as second order effect, is implemented to the method as well.

Geomagnetic Field Distribution in the Korean Peninsula by Spherical Harmonic Analysis (구면조화해석(球面調和解析)에 의(依)한 한반도내(韓半島內)의 지구자기장(地球磁氣場)의 분포(分布)에 관(關)한 연구(硏究))

  • Min, Kyung Duck;Lee, Sunhee
    • Economic and Environmental Geology
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    • v.12 no.2
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    • pp.95-104
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    • 1979
  • The position of any point on the earth's surface can be. represented in the spherical coordinates by surface spherical harmonics. Since geomagnetic field is a function of position on the earth, it can be also expressed by spherical harmonic analysis as spherical harmonics of trigonometric series of $a_m({\theta})$ cos $m{\phi}$ and $b_m({\theta})$ sin $m{\phi}$. Coefficients of surface spherical harmonics, $a_m({\theta})$ and $b_m({\theta})$, can be drawn from the components of the geomagnetic field, declination and inclination, and vice versa. In this paper, components of geomagnetic field, declination and inclination in the Korean peninsula are obtained by spherical harmonic analysis using the Gauss coefficients calculated from the world-wide magnetic charts of 1960. These components correspond to the values of normal geomagnetic field having no disturbances of subsurface mass, structure, and so on. The vertical and total components offer the zero level for the interpretation of geomagnetic data obtained by magnetic measurement in the Korean peninsula. Using this zero level, magnetic anomaly map is obtained from the data of airborne magnetic. prospecting carried out during 1958 to 1960. The conclusions of this study are as follows; (1) The intensity of horizontal component of normal geomagnetic field in Korean peninsula ranges from $2{\times}10^4$ gammas to $2.45{\times}10^4$ gammas. It decreases about 500 with the increment of $1^{\circ}$ in latitude. Along the same. latitude, it increases 250 gammas with the increment of $1^{\circ}$ in longitude. (2) Intensity of vertical component ranges from $3.85{\times}10^4$ gammas to $5.15{\times}10^4$ gammas. It increases. about 1000 gammas with the increment of $1^{\circ}$ in latitude. Along the same latitude, it decreases. 150~240 gammas with the increment of $1^{\circ}$ in longitude. Decreasing rate is considerably larger in higher latitude than in lower latitude. (3) Total intensity ranges from $4.55{\times}10^4$ gammas to $5.15{\times}10^4$ gammas. It increases 600~700 gammas with the increament of $1^{\circ}$ in latitude. Along the same latitude, it decreases 10~90 gammas. with the increment of $1^{\circ}$ in longitude. Decreasing rate is considerably larger in higher latitude as the case of vertical component. (4) The declination ranges from $-3.8^{\circ}$ to $-11.5^{\circ}$. It increases $0.6^{\circ}$ with the increment of $1^{\circ}$ in latitude. Along the same latutude, it increases $0.6^{\circ}$ with the increment of l O in longitude. Unlike the cases of vertical and total component, the rate of change is considerably larger in lower latitude than in higher latitude. (5) The inclination ranges from $57.8^{\circ}$ to $66.8^{\circ}$. It increases about $1^{\circ}$ with 'the increment of $1^{\circ}$ in latitude Along the same latitude, it dereases $0.4^{\circ}$ with the increment of $1^{\circ}$ in longitude. (6) The Boundaries of 5 anomaly zones classified on the basis of the trend and shape of anomaly curves correspond to the geologic boundaries. (7) The trend of anomaly curves in each anomaly zone is closely related to the geologic structure developed in the corresponding zone. That is, it relates to the fault in the 3rd zone, the intrusion. of granite in the 1st and 5th zones, and mountains in the 2nd and 4th zones.

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The Differential Effects of Acupuncture on Postures of Healthy Subjects (정상인의 자세에 따른 자침 효과의 차이)

  • Kim, Ji-Eun;Park, Kyung-Mo
    • Journal of Biomedical Engineering Research
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    • v.28 no.1
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    • pp.46-54
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    • 2007
  • Objective: The first aim of this study is to determine the effects of acupuncture on the autonomic nervous system (ANS) via Heart Rate (HR) and Pupil Size (PS), and to compare the effects of acupuncture on the subjects' ANS when they are in a sitting position with the effects when they are in a supine position. Methods: Ten healthy male subjects were randomized to receive either verum acupuncture stimulation in a sitting position (SitV), verum acupuncture stimulation in a supine position (SupV), sham acupuncture stimulation in a sitting position (SitS), and sham acupuncture stimulation in a supine position (SupS). Acupuncture stimulation was applied to Neguan point (PC6) on the forearm. The subject's electrocardiogram (ECG) and pupil size were recorded continuously from 5 min before stimulation to 12 min after stimulation. Results: Verum and sham acupuncture stimulation were found to have reduced heart rate (p<0.01) and to have increased pupil size (p<0.01) in all the subjects. But when the reduction in HR and the increment in PS after verum acupuncture stimulation (both sitting and supine position) were compared with those after sham acupuncture stimulation, it was found that the reduction in HR (74.48 and 73.47 bpm, p<0.063) and the increment of PS (7.32 and, 6.10 mm, p<0.001) after verum acupuncture stimulation were greater than those after sham acupuncture stimulation, and that the corresponding values were statistically significant. In addition, at the baseline, it was found that the subjects had a larger PS and a faster HR in a sitting position than when they did so in a supine position. And then the reduction and increment ratio in the subject's HR and PS when they underwent acupuncture stimulation in a sitting position was significantly different from the reduction and increment in their HR and PS when they underwent the procedure in a supine position-i.e., the reduction ratio in HR was greater when they underwent the procedure in a sitting position, and such reduction ratio was statistically significant (p<0.05). As for the increment in PS, it was greater when the subjects underwent the procedure in a supine position, and such increment was significant (p<0.05). Conclusion: Manual acupuncture stimulation on Neguan point (PC6) has more significant influence on the autonomic nervous system rather than sham acupuncture (tactile stimulation). And the position-induced different states of ANS have different influence on the acupuncture effect.