• Title/Summary/Keyword: equation of straight line

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A Study on measuring techniques of retrieval effectiveness (검색효율 측정척도에 관한 연구)

  • Yoon Koo Ho
    • Journal of the Korean Society for Library and Information Science
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    • v.16
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    • pp.177-205
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    • 1989
  • Retrieval effectiveness is the principal criteria for measuring the performance of an information retrieval system. This paper deals with the characteristics of 'relevance' of information and various measuring techniques of retrieval effectivess. The outlines of this study are as follows: 1) Relevance decision for evaluation should be devided into the user-oriented and the system-oriented decisions. 2) The recall-precision measure seems to be user-oriented, and the recall-fallout measure to be system-oriented. 3) Many of composite measures can not be justified III any rational manner unfortunately. 4) The Swets model has demonstrated that it yields, in general, a straight line instead of a curve of varying curvature and emphasized the fundamentally probabilistic nature of information retrieval. 5) The Cooper model seems to be a good substitute for precision and a useful measure for systems which ranked documents. 6) The Rocchio model were proposed for the evaluation of retreval systems which ranked documents, and were designed to be independent of cut-off. 7) The Cawkell model suggested that the Shannon's equation for entropy can be applied to measuring of retrieval effectiveness.

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Geometric analysis of mobile mapping images sequence

  • Kang, Zhizhong;Zhang, Zuxun
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.183-185
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    • 2003
  • Spatially referenced mobile mapping (MM) images contain rich information of man-made objects , e.g. road centerlines, buildings, light poles, traffic signs ,billboards and line trees etc. Therefore, the applications in transportation, urban 3D reconstruction, utility management are implemented increasingly. It’s a fundamental issue lies in MM image process that how to orient this image in the object space including interior orientation of camera and the exterior orientation of image. In this paper, the algorithm of automatic acquirement of DC (Digital Camera) parameters based on MM images is illustrated. And then, the mapping between image space and object space for MM images is described.

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The Relationship between Critical Load and Frequency of Sinusolidally Non-symmetrically Tapered Member (정현상 비대칭으로 Taper진 부재의 임계하중과 고유진동수와의 관계)

  • Lee, Hyuck;Hong, Jong-Kook;Lee, Soo-Gon
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.10a
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    • pp.59-66
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    • 2000
  • It is generally known that the lateral frequency( ω) of the vibration of a prismatic beam-column decreases according to the rele (equation omitted) (ω/sub 0/=natural frequency). In the cases of tapered members, the determination of P/ sub/ cr/(elastic critical load) and ω/ sub 0/ are not easy. Furthermore, the relationship between the compressive load and frequency can not be determined by the conventional analytical method. The axial force-frequency relationship of sinusolidally non-symmetrically tapered members with different shapes were investigated using the finite element method. To obtain the two eigenvalues, the axial thrust was increased step by step and the corresponding frequency was calculated. The result indicated that the axial thrust of the elastic critical load ratio and the square of the frequency ratio can be approximately represented in any case by a straight line. Finally, the linear relationship is also applicable to the sinusolidally non-symmetrically tapered member.

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The Experimental Study of EHD Printing for Different Nozzle Shapes (노즐 형상에 따른 전기수력학 프린팅의 실험적 연구)

  • Kim, Ji-Young;Nguyen, Vu Dat;Byun, Do-Young
    • Journal of the Korean Society of Visualization
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    • v.9 no.2
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    • pp.48-53
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    • 2011
  • The shape of nozzle cross-section plays an important role in stabilizing electrospray jet. The angle of contact line is governed based on the famous Young-Laplace equation. Compared to a round nozzle that has a constant curvature along the orifice, the square nozzle has four square corner edges and four straight edges that hold the meniscus in a different manner and is of interest in this study. By utilizing both square and round capillary nozzle, we examine the effect of nozzle shape in electrohydrodynamic jetting. The ejections were recorded with a high speed camera and analyzed to examine the jetting repeatability based on dynamic movement of meniscus. The result suggests that if the corner edges are not sharp, then its effect on repeatability is also limited.

Analysis on quench recovery of Au/YBCO thin film mender lines (Au/YBCO 박막 meander line의 퀜치회복에 대한 분석)

  • 김혜림;최효상;임해용;김인선;현옥배
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2001.02a
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    • pp.92-94
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    • 2001
  • We investigated quench recovery characteristics of Au/YBCO thin film meander lines. YB$a_{2}$$Cu_{3}$ $O_{7}$films were coated in-situ with a gold layer and patterned into 2 mm wide meander lines by photolithography. The limiters were tested with simulated fault currents at various source voltages. Resistance decreased first slowly and then rapidly to zero. Resistance vs. time curves for different source voltages fell on top of each other when translated horizontally. The slowly varying portion of data fell on straight lines of a slope on a semi-log scale at all source voltages. A heat balance equation reflecting heat loss from meander lines to surroundings explains these results quantitatively.

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The Interpretation on Underground Stress of Soil Layer Subjected to Moving Repeated Loads (이동하중에 의한 지중응력 해석)

  • Park Heung-Gyu;Kim Dae-Young
    • Journal of the Korean Geotechnical Society
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    • v.21 no.3
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    • pp.55-63
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    • 2005
  • In this research, we have compared and analyzed the value driven from theoretical equation of Boussinesque, Westergaard, Newmark and K$\"{o}$ogler with our experimental value from the model test on the underground stress distribution condition. As a result of conducting the Model Test, a change in the underground stress according to the loading was proven to be very similar to the tendency shown in the theories of Westergaard. A tendency of increasing in a straight line was shown in the underground stress according to the increase of loading. When compared to that of the theoretical equation, underground stress values were great until the depth of 15cm. However, after that depth, a tendency of showing smaller value than that of the theoretical equation was shown. Correlations between Moving Repeated Load (or) and Underground Stress ($\Delta\sigma$) show $\Delta\sigma\;=\; 0.009\cdot{\sigma}r-0.1$(depth 60 cm).

On Line Formation Analysis for Gradient Trail (경사지 원로의 선형 분석)

  • 김용수;나정화
    • Journal of the Korean Institute of Landscape Architecture
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    • v.14 no.1
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    • pp.45-60
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    • 1986
  • The purpose of the present studies is to establish more rational and practical planning theory for trails of gradient. The results drawn from this research work are as follow ; Mean angle according to topography of Jiga road is $3^{\circ}$33'in low part, $8^{\circ}$17'in middle park and $12^{\circ}$48'in high part. Here, we can find that the highest gradient of Jige roacl is $12^{\circ}$48, Which is showing the fact that jigs road is the most function road when we compare other roads. The regression coefficient between potential model pattern and calculuted model pattern is 0.8 withinTEX>$ 0~<5^{\circ}$, 0.5 within$ 6~10^{\circ}$, and 0.53 within $11~16^{\circ}$. The linear of these model pattern is lower in R & L value, and lager in S & A value according to be steeping gradient. It is thought that these fact are closely related with between human fatigue and R.S.A.L value. Accordingly, when we plan the trails of the gradient in city park, the from of trails is right to mix straight line with curve line within $0~5^{\circ}$, and sine wave close curve line within $6~10 ^{\circ}$, $l1~16^{\circ}$. But, in fact, It is absurd that potential model pattern is applied to the city park in park of corner, widely road and facilities. Therefore, It is thought that the study of this problems will be proceeded in the future. I can reduce the following equation in relation R & S by gradient ; 22 log (R-6.0)=47.96-$\delta$

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Creep properties and damage model for salt rock under low-frequency cyclic loading

  • Wang, Jun-Bao;Liu, Xin-Rong;Liu, Xiao-Jun;Huang, Ming
    • Geomechanics and Engineering
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    • v.7 no.5
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    • pp.569-587
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    • 2014
  • Triaxial compression creep tests were performed on salt rock samples using cyclic confining pressure with a static axial pressure. The test results show that, up to a certain time, changes in the confining pressure have little influence on creep properties of salt rock, and the axial creep curve is smooth. After this point, the axial creep curve clearly fluctuates with the confining pressure, and is approximately a straight line both when the confining pressure decreases and when it increases within one cycle period. The slope of these lines differs: it is greater when the confining pressure decreases than when it increases. In accordance with rheology model theory, axial creep equations were deduced for Maxwell and Kelvin models under cyclic loading. These were combined to establish an axial creep equation for the Burgers model. We supposed that damage evolution follows an exponential law during creep process and replaced the apparent stress in creep equation for the Burgers model with the effective stress, the axial creep damage equation for the Burgers model was obtained. The model suitability was verified using creep test results for salt rock. The fitting curves are in excellent agreement with the test curves, so the proposed model can well reflect the creep behavior of salt rock under low-frequency cyclic loading. In particular, it reflects the fluctuations in creep deformation and creep rate as the confining pressure increasing and decreasing under different cycle periods.

Studies on the Polarographic Behavior of Elemental Sulfur (원소 유황의 Polarograph 거동에 관한 연구)

  • 김준용;장순자
    • YAKHAK HOEJI
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    • v.22 no.4
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    • pp.201-206
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    • 1978
  • The analysis of elemental sulfur by polarography has already been reported in the literature. Only a discussion of the more important factors influencing the analysis is here presented. (1) The effects of pH on the reduction of elemental sulfur are pronounced and the use of buffered solutions for the analysis of elemental sulfur is necessary. The authors found that a pH of 4-6 was found to be reproducible polarograms by use of D.C. polarograph. However, in alkali solvents the plateau of elemental sulfur has a pronounced dip if the concentration of sulfur is as much as 30ppm. (2) A.C. polarographic method shows a very high sensitivity in the case of sulfur reduction, so that the very low concentration of sulfur can easily be determined (about 1ppm). (3) The characteristics of sulfur wave can be formulated according to Stackelberg-Hauck-Hans equation. It was found that the curve of the peak potential of elemental sulfur in A.C. polarography versus logarithm of sulfur concentration was obtained to be straight line with the slope of 29.6 millivolts. This result was well agreed with theoretical consideration. (4) It was assumed that this polarographical methods were applicable to micro-analysis of elemental sulfur in crude oil and its petrochemical products, precipitated sulfur, and sulfur ointments with accuracy and rapidity.

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Joint disturbance torque analysis for independent joint controlled robots and its application in optimal path placement (독립관절제어 로봇의 관절외란해석과 최적경로위치 문제의 해법)

  • Choi, Myung-Hwan
    • Journal of Institute of Control, Robotics and Systems
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    • v.4 no.3
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    • pp.342-348
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    • 1998
  • A majority of industrial robots are controlled by a simple joint servo control of joint actuators. In this type of control, the performance of control is greatly influenced by the joint interaction torques including Coriolis and centrifugal forces, which act as disturbance torques to the control system. As the speed of the robot increases, the effect of this disturbance torque increases, and hence makes the high speed - high precision control more difficult to achieve. In this paper, the joint disturbance torque of robots is analyzed. The joint disturbance torque is defined using the coefficients of dynamic equation of motion, and for the case of a 2 DOF planar robot, the conditions for the minimum and maximum joint disturbance torques are identified, and the effect of link parameters and joint variables on the joint disturbance torque are examined. Then, a solution to the optimal path placement problem is propose that minimizes the joint disturbance torque during a straight line motion. The proposed method is illustrated using computer simulation. The proposed solution method can be applied to a class of robots that are controlled by independent joint servo control, which includes the vast majority of industrial robots.

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