• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.10 s.253
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• pp.942-949
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• 2006

A lumped model is proposed to predict liquid ejection characteristics of a thermally driven inkjet print head. The model is based on a two-dimensional heat conduction equation, an empirical pressure-temperature equation and a nonlinear hydraulic flow-pressure equation. It has been simulated through the construction of an equivalent R-C circuit, and subsequently analyzed using SIMULINK and a circuit simulation tool, PLECS. Using the model, heating and cooling characteristics of the head are predicted to be in agreement with the IR temperature measurements. The effects of the head geometry on the drop ejection are also analyzed using the nonlinear hydraulic model. The present model can be used as a design tool for a better design of thermal inkjet print heads.

• Imaging Science in Dentistry
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• v.43 no.3
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• pp.191-196
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• 2013

Purpose: This study assessed the accuracy of linear and angular measurements on panoramic radiographs taken at different positions in vitro. Materials and Methods: Two acrylic models were fabricated from a cast with normal occlusion. Straight and $75^{\circ}$ mesially and lingually angulated pins were placed, and standardized panoramic radiographs were taken at standard position, at an $8^{\circ}$ downward tilt of the occlusal plane compared to the standard position, at an $8^{\circ}$ upward tilt of the anterior occlusal plane, and at a $10^{\circ}$ downward tilt of the right and left sides of the model. On the radiographs, the length of the pins above (crown) and below (root) the occlusal plane, total pin length, crown-to-root ratio, and angulation of pins relative to the occlusal plane were calculated. The data were subjected to repeated measures ANOVA and LSD multiple comparisons tests. Results: Significant differences were noted between the radiographic measurements and true values in different positions on both models with linear (P<0.001) and those with angulated pins (P<0.005). No statistically significant differences were observed between the angular measurements and baselines of the natural head posture at different positions for the linear and angulated pins. Conclusion: Angular measurements on panoramic radiographs were sufficiently accurate and changes in the position of the occlusal plane equal to or less than $10^{\circ}$ had no significant effect on them. Some variations could exist in the pin positioning (head positioning), and they were tolerable while taking panoramic radiographs. Linear measurements showed the least errors in the standard position and $8^{\circ}$ upward tilt of the anterior part of the occlusal plane compared to other positions.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.735-739
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• 2005

This paper presents a new system to estimate the head pose of human in interactive indoor environment that has dynamic illumination change and large working space. The main idea of this system is to suggest a new morphological feature for estimating head angle from stereo disparity map. When a disparity map is obtained from stereo camera, the matching confidence value can be derived by measurements of correlation of the stereo images. Applying a threshold to the confidence value, we also obtain the specific morphology of the disparity map. Therefore, we can obtain the morphological shape of disparity map. Through the analysis of this morphological property, the head pose can be estimated. It is simple and fast algorithm in comparison with other algorithm which apply facial template, 2D, 3D models and optical flow method. Our system can automatically segment and estimate head pose in a wide range of head motion without manual initialization like other optical flow system. As the result of experiments, we obtained the reliable head orientation data under the real-time performance.

• International Journal of Automotive Technology
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• v.7 no.1
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• pp.69-74
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• 2006

Residual stresses are introduced in aluminum cylinder head during quenching at the end of the T6 heat treatment process. Tensile residual stress resulted from quenching is detrimental to fatigue behavior of a cylinder head when it is overlapped with stresses of engine operation load. Quenching simulation has been performed to assess the distribution of residual stress in the cylinder head. Analysis revealed that in-homogeneous temperature distribution led to high tensile residual stress at the foot of the long intake port, where high stresses of engine operation load are expected. Measurements of residual stress have been followed and compared with the calculated results. Results successfully proved that high tensile residual stress, which was large enough to accelerate fatigue failure of the cylinder head, are formed during quenching process at the end of heat treatment at the same critical position. Effect of quenching parameters on the distribution of residual stress in cylinder head has been investigated by choosing different combination of heat treatment parameters. It was demonstrated that changes of quenching parameters led to more homogeneous temperature distribution during cooling and could reduce tensile residual stress at the critical region of the cylinder head used in this study.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.270-280
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• 2007

The objectives of study are to investigate the relationship between Sasang Constitution(四象醫學) and measuring items of the head and face and to develop useful diagnosis standard of Sasang Constitution. Subjects took QSCCII(Questionnaire for the Sasang Constitution Classification II) tests repeatedly at an interval of one year and were diagnosed as same constitutions. The 9 Items were measured by Martin-type anthropometric method in 112 subjects. Compared with measurements of 3 constitutions, the mean values in Taeeum-in(太陰人) showed highest and there were significant differences in 7 items between Taeeum-in(太陰人) and other constitutions. Especially, Measurements of Bitragus to Submandibular Arc Length(BSAL) item and Bitragus to Menton Arc Length(BMAL) item showed significant differences between Taeeum-in(太陰人) male and other constitutions male. It seems that BSAL and BMA items can differentiate Taeeum-in(太陰人) from other constitutions and these items have possibility to be a diagnosis standard of Sasang Constitution.

• Journal of Korean Clinical Health Science
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• v.10 no.2
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• pp.1587-1593
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• 2022

Purpose. This study was to investigate the degree of refractive error that occurs depending on the measurement location of the subject when performing a refraction test using the automatic refractor. Methods. When performing the auto-refraction test, measurements were taken while increasing the distance between the forehead and the forehead rest, and the measurements were made by tilting the head clockwise and counterclockwise. Results. During the auto-refraction test, significant refractive error occurred when the forehead was not attached to the forehead support or the subject's head was turned clockwise or counterclockwise. Conclusions. When performing a refraction test using an automatic refractor, the examiner will have to pay attention to whether the subject's forehead is in close contact with the forehead rest, and whether the head is tilted.

• Anatomy and Cell Biology
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• v.56 no.1
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• pp.39-45
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• 2023

Fixation of radial head fracture with minimally invasive posterior approach remains a significant challenge. The aim of this study was to determine the feasibility of trans-anconeus posterior elbow approach and to observe lateral ulnar collateral ligament (LUCL) in extended elbows. This cadaveric study was performed in twenty upper limbs of fresh fixed adult male cadavers. An oblique incision was made in the middle segment of anconeus until the lateral ligament complex and the joint capsule had been revealed. A deep dissection was explored to observe the anatomical relationship of the LUCL to the anconeus. Measurements of the LUCL were recorded while the elbow was fully extended. The mean distance between the edge of the radial head and the proximal insertion of the LUCL was 13.3 mm (11.5-16.2 mm); the mean distance between the edge of the radial head and the distal insertion of the LUCL was 20.9 mm (19.2-23.4 mm); the distance between the edge of the radial head and the distal edge of the annular ligament was 11.2 mm (8.22-11.7 mm). By estimate correlation of the previous measurements, the direct and accessible way to expose the posterolateral articular capsule of the elbow joint was through a window in medial 2/3 of the middle segment of anconeus muscle. These trans-anconeus approach is useful. It provides good visualization, facilitates applying the implants, and lessens the risk of radial nerve injury. Awareness of the anatomy is mandatory to avoid injury of LUCL.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.1
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• pp.99-106
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• 1997

The purpose of this study was to compare & to find out the variability of head film measurements (and marks identification) between Fuji computed radiographic cephalometry and conventional cephalometry. 28 Korean adults were selected. Lateral cephalometric FCR film and conventional cephalometric film of each subject was taken. Four investigators identified 24 cephalometric landmarks on lateral cephalometric FCR film and conventional cephalometric film. The comparable measurements between lateral cephalometric FCR film and conventional cephalometric film were statistically analysed. The results were as follows : 1. In FCR film & conventional film, coefficient of variation (C.V.) of 24 landmarks was taken horizonta1ly & vertically. There is no significant difference of rank order of landmarks in C.V. between two films. 2. In comparison of significant differences of landmarks variability between FCR film & conventional film, horizontal value of coefficient of variation, showed significant differences in four landmarks among twenty-four landmarks, but vertical value of coefficient of variation showed significant differences in sixteen landmarks among twenty-four landmarks. FCR film showed significantly less variability than conventional film in 17 subjects among 20(4+16) subjects that showed significant difference.

• The International Journal of Costume Culture
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• v.2 no.1
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• pp.43-53
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• 1999

The research analyzs characteristics of body types for the Chineses women based on the different life style and to compare the differences of body type with Korean women. The measurement had took in Beijing and Seoul in 1999. As a result of comparing Chinese and Korean women'body measurements, it was found that Chinese women are shorter and obser than Korean women. Besides, chinese arms and upper body are shorter, and their body is thicker compared with their relatively flat chest. After all, Cheinese women'chests are more voluminous, while their shoulders are drooped more, although their shoulder size is almost as same as Korean women'. By used factor analysis, 8 factors were extracted from body measurements : body obesity, vertical body size, ankle and knee sizes, head size, front upper body length, shoulder size, form and size of neck and upper chest, drooping of shoulders, and size of hip. It was found that Chinese college women are obser with larger vertical body length and front upper body length. And their shoulders are more drooped with larger hip. But two nations'female students did not show any differences in the sizes of ankles, knees, head and shoulders.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.441-448
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• 1994

Postweaning performance data were obtained on 187 group fed purebred Angus calves from 12 selected sires (six high and six low feed conversion sires) in 1985 and 1986. The objective of this portion of the study was to develop prediction equations for feed conversion from a stepwise regression analysis. Variables measured were on-test weight (ONTSTWT), on-test age (ONTSTAG), five weights by 28-d periods, seven linear body measurements: heart girth (HG), hip height (HH), head width (HDW), head length (HDL), muzzle circumference (MC), length between hooks and pins (HOPIN) and length between shoulder and hooks (SHHO), and backfat thickness (BF). Stepwise regressions for maintenance adjusted feed conversion (ADJFC) and unadjusted feed conversion (UNADFC) over the first 140 d of the test, and total feed conversion (FC) until progeny reached 8.89 mm of back fat were obtained separately by conversion groups and sexes and for combined feed conversion groups and sexes. In general, weights were more important than linear body measurements in prediction of feed utilization. To some extent this was expected as weight is related directly to gain which is a component of feed conversion. Weight at 112 d was the most important variable in prediction of feed conversion when data from both feed conversion groups and sexes were combined. Weights at 84 and 140 d were important variables in prediction of UNADFC and FC, respectively, of bulls. ONTSTWT and weight at 140 d had the highest standardized partial regression coefficients for UNADFC and ADJFC, respectively, of heifers. Results indicated that linear measurements, such as MC, HDL and HOPIN, are useful in prediction of feed conversion when feed in takes are unavailable.