• Title/Summary/Keyword: projected area

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EFFICIENT THERMAL MODELING IN DEVELOPMENT OF A SPACEBORNE ELECTRONIC EQUIPMENT

  • Kim Jung-Hoon;Koo Ja-Chun
    • Bulletin of the Korean Space Science Society
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    • 2004.10b
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    • pp.270-273
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    • 2004
  • The initial thermal analysis needs to be fast and efficient to reduce the feedback time for the optimal electronic equipment designing. In this study, a thermal model is developed by using power consumption measurement values of each functional breadboard, that is, semi-empirical power dissipation method. In modeling heat dissipated EEE parts, power dissipation is imposed evenly on the EEE part footprint area which is projected to the printed circuit board, and is called surface heat model. The application of these methods is performed in the development of a command and telemetry unit (CTU) for a geostationary satellite. Finally, the thermal cycling test is performed to verify the applied thermal analysis methods.

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THE STUDIES ON STANDARDIZED PROJECTION FOR TEMPOROMANDIBULAR JOINT (악관절의 규격화 촬영에 관한 연구)

  • Park Tae Won
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.12 no.1
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    • pp.63-67
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    • 1982
  • The author modified the Aquard 100 head holder device from Denar Co. to be adequate to the Koreans and to enhance the standardization and reproducibility of the temporomandibular joint radiographs. The results were obtained as follows; 1. The projected central ray was at an angle of 25 degrees. 2. Standardization of patients head position was obtained by means of vertical and horizontal bar which were attached to the head holder. 3. Arbitrary 3 points (A.B.C.) which were on the TMJ area of dry skull were measured for the identification of reproducibility. 4. Measured distances in dry skull were as follow; A-B, 28.0±0.25, B-C 11.9±0.25 and C-A 30.4±0.21, in closed position.

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Next Generation Fiber Length Measurement

  • Tiikkaja, Esa;Sopenlehto, Taina
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.32 no.5
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    • pp.54-59
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    • 2000
  • The next generation fibre size analyser has been developed in Kajaani based on over 15 years experience in fibre measurement. This new FiberLab-analyser can measure fibre length both along the fibre centre line and as projected. The cross-sectional measurements of fibre are in principle similar to the earlier version FiberLab. Measured data are generally displayed in distributions. Some new calculations have been added, for example the fibres cross sectional area and fibre volume index both available as distributions as well. The performance of the FiberLab measurement is verified against the manual microscopic testing. These tests show that the new image analysis-based measurement well matches with the manual methods.

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Flow Pattern Identification of Vertical Upward Two-Phase Flow Using the Attractor-Density-Map Analysis of the Void Fraction Signal in the Nonlinear Phase Space (비선형 위상공간에서의 기포 분율 신호의 끌개밀도분식을 이용한 수직 상향 이상유동의 유동패턴분류)

  • Kim, Nam-Seok;Lee, Jae-Young
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.11
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    • pp.1398-1406
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    • 2004
  • The nonlinear signals from an impedance meter for the area average void fraction in two-phase flow have been analyzed to construct a phase space trajectory. The pseudo phase space was constructed with the time delay and proper dimensions. The time delay and the embedding dimension were chosen by the average mutual information and by the false nearest neighborhood, respectively. The attractor-density-map of projected states was used to produce the two dimensional probability distribution functions (2D-PDF). Since the developed 2D-PDF showed clear distinction of the flow patterns, the flow regime identification was made with three rules and with the 2D-PDF. Also, the transition criteria of Mishima-Ishii agree well with the present results.

Guide plates on wind uplift of a solar collector model

  • Chung, K.M.;Chang, K.C.;Chen, C.K.;Chou, C.C.
    • Wind and Structures
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    • v.16 no.2
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    • pp.213-224
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    • 2013
  • One of the key issues affecting the promotion of solar water heaters in Taiwan is the severe impact of typhoon each year. An experimental study was conducted to investigate the wind uplift characteristic of a solar collector model with and without a guide plate. The guide plate with different lengths and orientations with respect to wind direction was adopted. It is found that the wind uplift of a solar collector is associated with the tilt angle of the flat panel as expected. A cavity formed between the guide plate and the flat panel has a significant effect on the distributions of streamwsie and lateral pressure. Reduction in uplift is essentially coupled with the projected area of a guide plate on the lower surface of the tilt flat panel.

Effect of a vertical guide plate on the wind loading of an inclined flat plate

  • Chung, Kung-Ming;Chou, Chin-Cheng;Chang, Keh-Chin;Chen, Yi-Jun
    • Wind and Structures
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    • v.17 no.5
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    • pp.537-552
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    • 2013
  • Wind tunnel experiments were performed to study the wind loads on an inclined flat plate with and without a guide plate. Highly turbulent flow, which corresponded to free-stream turbulence intensity on the flat roof of low-rise buildings, was produced by a turbulence generation grid at the inlet of the test section. The test model could represent a typical solar collector panel of a solar water heater. There are up-stream movements of the separation bubble and side-edge vortices, more intense fluctuating pressure and a higher bending moment in the turbulent flow. A guide plate would result in higher lift coefficient, particularly with an increased projected area ratio of a guide plate to an inclined flat plate. The value of lift coefficient is considerably lower with increased free-stream turbulent intensity.

The Supply and Demand Projection of Physicians in the Medical Service Area (2010년까지의 진료부문 의사인력수급 추계)

  • 박현애;최정수;류시원
    • Health Policy and Management
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    • v.1 no.1
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    • pp.136-152
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    • 1991
  • The study was conducted to project supply and demand of the physicians from year 1991 to year 2010 based on the analysis of supply and demand of the physicians up to year 1989. Results of the study will provide information for the physicians manpower planning of the 7th 5-year Economic Social Development Planning(1992-1996) and contribute to the overall health manpower planning for the 21the century. It is projected that physician will be oversupplied from the very near future based on the current productivity or underestimated based on the optimal productivity. Thus, it is desirable not to change size of training and education during the 7the 5-year planning period and re-examine the status of the physician manpower at the end of the 7th 5-year period taking into consideration medical services utilization pattern, patients' satisfaction, and physicians' productivity.

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Comparative Assessment of Virtual Garments using Direct and Manual Avatars (가상아바타에 따른 가상의복의 비교평가)

  • Lim, Ho-Sun;Istook, Cynthia L.
    • The Research Journal of the Costume Culture
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    • v.19 no.6
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    • pp.1359-1371
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    • 2011
  • The purpose of this paper is to compare two avatars made using direct and manual methods and to evaluate the fit and appearance of two virtual garments on the direct and manual avatars. In this study, two subjects were measured by $[TC]^2$ body scanner and the avatars and virtual garments were created by OptiTex software. The direct avatar was made by the direct importation of 3D body scan data and the manual avatar was made by manual input from extracted body measurement. Two virtual garments in a tank-top were evaluated by distance, transparency, and stretch maps. In the results of comparing difference of the direct and manual avatars, the bust and back of the manual avatar are protruded slightly more than that of the direct avatar and the manual avatar is slightly larger dimensions at the bust, waist, abdomen, and hip area in the side view in case of subject 1 and 2. In the results of comparing difference of the fit and appearance of two virtual garments on the direct and manual avatars, in case of subject 1 and 2, the back of the virtual garment on the manual avatar are protruded more than that of the direct avatar. Also, the ease in the bust area of the virtual garment on the manual avatar with a projected bust area was smaller than that of the virtual garment on the direct avatar and the stretch of that of the manual avatar was also high in the bust area. The results of this study are expected to be used as basic information in the apparel industry using virtual try-on technology.

A Study on the Behaviour of Fish Schools in the Process of Catch of the Purse Seine Fishing Method (선망어법의 어획과정에 있어서 어군행동에 관한 연구)

  • Park, Jeong-Sik;Kim, Seok-Jong;Kim, Sam-Gon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.33 no.3
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    • pp.173-182
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    • 1997
  • This study is a basic research in purse seine fishery : on the behaviour of fish schools of tilapia Tilapia mossambica in the process of catch of the purse seine fishing method. The experiment was carried out for the mackerel purse seine which using of power block by fishing fleet system in the near sea of Cheju Island and as a forecast in the near future on the purse seine fishing, using of triplex net winch by one boat system in the near sea of Norway. These model purse seines were made of the scale of 1/180 of its full scale. The model purse seine test on the escaping behaviour of fish school by gap, area reducing of gap and tension of purse line was carried out in the stagnant water of experimental water tank. Designing and testing for the model purse seines were based on the Tauti's law. The results obtained were as follows : 1. When the time for the completing of pursing was 20 minutes, average swimming speed of fish school through a gap was 9.71cm/sec for powerblock seine and 9.97cm/sec for triplex seine. 2. In the case of pursing time in actual value was 20minutes, at 50 percent of the pursing, swimming behaviour of fish school in purse seine was 10% to I section, 80% to II section, 10% to III sectional direction for powerblock seine and a similar tendency for triplex seine. 3. In the case of pursing time in actual value was 20 minutes, at the time of 10 minutes have proceeded since then, area reducing rate of gap of the seine in projected front view was 63.5% for powerblock seine and 67.5% for triplex seine. 4. In the case of pursing time in actual value was 20 minutes, escaping rate of fish school by gap in projected front view was 70% for powerblock seine and 30% for triplex seine. Maximum tension of purse line was about 8.1 tons for powerblock seine and about 8.3 tons for triplex seine.

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Cone Resistivity Penetrometer for Detecting Thin-Layered Soils (협재층 탐지를 위한 선단비저항 콘)

  • Yoon, Hyung-Koo;Jung, Soon-Hyuck;Kim, Rae-Hyun;Lee, Jong-Sub
    • Journal of the Korean Geotechnical Society
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    • v.26 no.8
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    • pp.15-25
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    • 2010
  • The thin-layered sand seam in clay affects the soil behavior. Although the standard cone penetrometer (A: $10cm^2$) have been used to evaluate the thin-layered soil, the smaller diameter cone penetrometer have been commonly recommended because of the high resolution. The purpose of this study is the development and application of the Cone Resistivity Penetrometer (CRP), which detects qc, fs, and electrical resistivity at cone tip for the evaluation of thin layered soils. Two sizes of the CRP are developed for the laboratory and field test. The projected areas of CRP for the laboratory and field tests are $0.78cm^2$ (d: 1.0 cm) and $1.76cm^2$ (d: 1.5 cm), repectively. The length of friction sleeve is designed in consideration of ratio of the projected area to the friction sleeve area. The application tests are carried out by using the artificially prepared thin-layered soils in the laboratory. In addition, the field tests are conducted at the depth of 6 to 15 m in Kwangyang. In the laboratory test, the measured electrical resistivity and cone tip resistance detect the soil layers. Moreover, in the field test the CRP investigates the three thin-layered soils. This study suggests that the CRP may be a useful tool for detecting thin-layered in soft soils.