• Title/Summary/Keyword: 2-dimensional measurement

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Study on the extraction of characteristics of LTCC RF components (LTCC RF 소자 특성 추출에 관한 인구)

  • 유찬세;이우성;강남기;박종철
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2002.05a
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    • pp.214-218
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    • 2002
  • So far, many kinds of researches on the ceramic chip components and MCM-C RF module especially on the 3-dimensional ceramic module using embedded passives have been performed. LTCC system has many kinds of advantages, like low lass, low cost of process, stability of process etc.. But it's so hard to adjust the characteristics of passives in ceramic module after fabrication. So the exact prediction of behavior of components in high frequency region upper than 2 GHz must be made. In this procedure, the exact measurement is need. In this study, many kinds of measurement Jigs are compared and optimized, and measurement methods of each parameter are designed.

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Three-Dimensional Volume Assessment Accuracy in Computed Tomography Using a Phantom (모형물을 이용한 전산화 단층 촬영에서 3차원적 부피측정의 정확성 평가)

  • Kim, Hyun-Su;Wang, Ji-Hwan;Lim, Il-Hyuk;Park, Ki-Tae;Yeon, Seong-Chan;Lee, Hee-Chun
    • Journal of Veterinary Clinics
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    • v.30 no.4
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    • pp.268-272
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    • 2013
  • The purpose of this study was to assess the effects of reconstruction kernel, and slice thickness on the accuracy of spiral CT-based volume assessment over a range of object sizes typical of synthetic simulated tumor. Spiral CT scanning was performed at various reconstruction kernels (soft tissue, standard, bone), and slice thickness (1, 2, 3 mm) using a phantom made of gelatin and 10 synthetic simulated tumors of different sizes (diameter 3.0-12.0 mm). Three-dimensional volume assessments were obtained using an automated software tool. Results were compared with the reference volume by calculating the percentage error. Statistical analysis was performed using ANOVA and setting statistical significance at P < 0.05. In general, smaller slice thickness and larger sphere diameters produced more accurate volume assessment than larger slice thickness and smaller sphere diameter. The measured volumes were larger than the actual volumes by a common factor depending on slice thickness; in 100HU simulated tumors that had statistically significant, 1 mm slice thickness produced on average 27.41%, 2 mm slice thickness produced 45.61%, 3 mm slice thickness produced 93.36% overestimates of volume. However, there was no statistically significant difference in volume error for spiral CT scans taken with techniques where only reconstruction kernel was changed. These results supported that synthetic simulated tumor size, slice thickness were significant parameters in determining volume measurement errors. For an accurate volumetric measurement of an object, it is critical to select an appropriate slice thickness and to consider the size of an object.

A Study on 2-Dimensional Sound Source Tracking System III - mainly on digital signal processing - (2차원적 음원추적에 관한 연구III - 디지털 신호처리를 중심으로 -)

  • 문성배;전승환
    • Journal of the Korean Institute of Navigation
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    • v.24 no.5
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    • pp.443-450
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    • 2000
  • Before some experiments were carried out with analog bandpass filter which used for filtering the noise included in sound source signal. And this filter was constituted by condenser, register and operational amplifier. Hut these elements made the phase characteristics to differentiate in each sensing channel and cause a little of measurement error. We made new measurement system that was substituted digital filter for the analog filter in order to develop the optimal system which could find the time delay between each sensors with high accuracy. This paper describes the new system's constitution and the function of each parts. Specially three digital filters were designed and applied to the digital signal processing Part. And a series of experiments were carried out with the source's distance 9.53meters and the random bearing interval within the limits of $0^{\circ}$ ~ $180^{\circ}$. As a result, we have recognized that the accuracy of measurements were differentiated by the methods what kind of digital filter were adopted. And we have confirmed the facts that IIR LPF was suitable for sound source's bearing measurement and FIR LPF reduced the range measurement error.

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Three-dimensional Capsular Volume Measurements in Multidirectional Shoulder Instability

  • Jun, Yong Cheol;Moon, Young Lae;Elsayed, Moustafa I.;Lim, Jae Hwan;Cha, Dong Hyuk
    • Clinics in Shoulder and Elbow
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    • v.21 no.3
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    • pp.134-137
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    • 2018
  • Background: In a previous study undertaken to quantify capsular volume in rotator cuff interval or axillary pouch, significant differences were found between controls and patients with instability. However, the results obtained were derived from two-dimensional cross sectional areas. In our study, we sought correlation between three-dimensional (3D) capsular volumes, as measured by magnetic resonance arthrography (MRA), and multidirectional instability (MDI) of the shoulder. Methods: The MRAs of 21 patients with MDI of the shoulder and 16 control cases with no instability were retrospectively reviewed. Capsular areas determined by MRA were translated into 3D volumes using 3D software Mimics ver. 16 (Materilise, Leuven, Belgium), and glenoid surface area was measured in axial and coronal MRA views. Then, the ratio between capsular volume and glenoid surface area was calculated, and evaluated with control group. Results: The ratio between 3D capsular volume and glenoid surface area was significantly increased in the MDI group ($3.59{\pm}0.83cm^3/cm^2$) compared to the control group ($2.53{\pm}0.62cm^3/cm^2$) (p<0.01). Conclusions: From these results, we could support that capsular volume enlargement play an important role in MDI of the shoulder using volume measurement.

A Method for Identification of Harmful Video Images Using a 2-Dimensional Projection Map

  • Kim, Chang-Geun;Kim, Soung-Gyun;Kim, Hyun-Ju
    • Journal of information and communication convergence engineering
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    • v.11 no.1
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    • pp.62-68
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    • 2013
  • This paper proposes a method for identification of harmful video images based on the degree of harmfulness in the video content. To extract harmful candidate frames from the video effectively, we used a video color extraction method applying a projection map. The procedure for identifying the harmful video has five steps, first, extract the I-frames from the video and map them onto projection map. Next, calculate the similarity and select the potentially harmful, then identify the harmful images by comparing the similarity measurement value. The method estimates similarity between the extracted frames and normative images using the critical value of the projection map. Based on our experimental test, we propose how the harmful candidate frames are extracted and compared with normative images. The various experimental data proved that the image identification method based on the 2-dimensional projection map is superior to using the color histogram technique in harmful image detection performance.

The Measurement of Femoral Neck Anteversion by 3D Modeling of Femoral Major Axes (대퇴골 주요축의 3차원 모델링에 의한 전염각의 측정)

  • Kim, Jun-Sik;Kim, Seon-Il
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.341-350
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    • 1998
  • The accurate measurement of the femoral anteversion is important for the derotational osteotomy. To estimate femoral anteversion, following three major parameters are required; the neck axis, the long axis, and the knee axis. Conventional methods on the basis of 2D images are ambiguous to determine these major axes. As the femur has a complex 3 dimensional structure, the 3 dimensional model should be applied for accurate and reliable measurement of femoral anteversion. In this thesis, we model femur and define three parameters. The neck axis is defined from the femoral head and neck model. The long axis is determined from the cylindrical model of the femoral shaft. The knee axis is also determined from the model of femoral condyles. According to the definition of the femoral anteversion, the femoral anteversion is efficiently estimated from these models. 20 specimens were tested by the conventional 2D imaging method and 3D imaging method witch was developed by authors and the new 3D modeling method. The study provides accurate, fast and human factor free measurement for femoral anteversion.

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Difference of The Cardiac Structure and Function Depending on Obesity Level of Healthy Adults

  • Shin, Kyung-A;Hong, Seung-Bok
    • Biomedical Science Letters
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    • v.17 no.2
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    • pp.141-149
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    • 2011
  • The purpose of this study was to find out any difference and correlation between the cardiac structure and its function according to the level of obesity as evaluated by waist measurement and BMI (body mass index) in healthy adults. For research subjects, the study selected a final 519 subjects excluding 198 subjects aged 55 or over out of 717 subjects who received echocardiography through a medical checkup at J General Hospital. For the criteria for obesity, men were defined as being obese in case their waist measurement was over 90 cm, whereas women were defined as being obese in case their waist measurement was over 80 cm. Also, regarding the BMI criteria, in case a person's BMI was 30 kg/$m^2$, the subject was classified as belonging to an obese group, and in case a person's BMI was between 25 kg/$m^2$ and 30 kg/$m^2$, the subject was classified as belonging to an overweight group. Concerning the evaluation of cardiac structure and function, they were evaluated using two-dimensional, M-mode, doppler echocardiography. According to the stage of obesity in accordance with waist measurement and BMI, the cardiac structure showed both eccentric and centripetal changes, and the cardiac function was also discovered to show differences according to the stage of obesity. In addition, also in the overweight group, which is a prior stage to obesity, out of the criteria for obesity classification according to BMI, there were differences in the cardiac structure and function. Also, both the waist measurement and BMI were found to have a correlation with cardiac structure and diastolic function. Consequently, cardiac structure and function are correlated with BMI and waist measurement, which are anthropometrical variables, and obesity is assumed to induce not only structural change but also functional change of the heart.

A Study on the Fluid Flew with Ultrasonic Forcing by PIV Measurement (초음파가 가진된 유체유동의 PIV계측에 의한 연구)

  • 주은선;이영호;나우정;정진도
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.6
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    • pp.1281-1290
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    • 2001
  • A study on the fluid flow with ultrasonic forcing is carried out to obtain data for the turbulence enhancement. A large water tank is made of the transparent acrylic plates and a horizontal flow field is given by setting two acrylic tubes to face mutually on a horizontal line. A 2-dimensional PlV system which is composed of a continuous-output 4W Argon-ion laser, a high-speed video camera, a PC based by an image grabber and a high resolution monitor is used to investigate characteristics of the complex turbulence flow field. And a 2MHz ultrasonic transducer is used fur ultrasonic vibration forcing. Some experiments are carried out at Reynolds numbers of 2,000 and 4,000 and at 7 angles of ultrasonic incidence. In results, the flew velocity vector distribution, kinetic energy and turbulence intensity in both cases of with and without ultrasonic forcing are examined, compared and discussed by using PIV measurement. It is clarified that the ultrasonic forcing into flow field is valid to obtain the turbulence enhancement.

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A Study on 3-D Shape Measurement and Application by Using Digital Projection Moire (II) (디지털 영사식 무아레를 이용한 3차원 형상 측정과 응용에 관한 연구(II))

  • Ryu, Weon-Jae;Kang, Young-June;Rho, Hyung-Min;Lee, Dong-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.5
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    • pp.62-67
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    • 2007
  • A simple dimension measuring method for the measurement of human bust has been developed using projection moire. The 3-D data of a human bust was calculated from the 2dimensional image information obtained by the stripe using projection moire. The creation of 3-D geometric shape by digitizing real objects has been widely investigated in reverse engineering(RE). This procedure generally consists of three basic steps: data capture, data alignment and model reconstruction. In order to achieve a complete model, multiple scans must be taken and aligned.

Temperature Field Measurement of Non-Isothermal Jet Flow Using LIF Technique (레이저형광여기(LIF)를 이용한 비등온 제트유동의 온도장 측정)

  • Yoon, Jong-Hwan;Lee, Sang-Joon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.10
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    • pp.1399-1408
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    • 2000
  • A 2-dimensional temperature field measurement technique using PLIF (Planar Laser Induced Fluorescence) was developed and it was applied to an axisymmetric buoyant jet. Rhodamine B was used as a fluorescent dye. Laser light sheet illuminated a two-dimensional cross section of the jet. The intensity variations of LIF signal from Rhodamine B molecules scattered by the laser light were captured with an optical filter and a CCD camera. The spatial variations of temperature field of buoyant jet were derived using the calibration data between the LIF signal and real temperature. The measured results show that the turbulent jet is more efficient in mixing compared to the transition and laminar jet flows. As the initial flow condition varies from laminar to turbulent flow, the entrainment from ambient fluid increases and temperature decay along the jet center axis becomes larger. In addition to the mean temperature field, the spatial distributions of temperature fluctuations were measured by the PLIF technique and the result shows the shear layer development from the jet nozzle exit.