• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.1
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• pp.55-65
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• 2024

This study aimed to assess the accuracy of tooth widths, intermolar widths, and arch lengths acquired through two intraoral scanners, including iTero Element Plus Series (Align Technology, Santa Clara, CA, USA) and Trios 4 (3Shape, Copenhagen, Denmark), specifically on mixed dentition. A total of 30 subjects were divided into 2 groups, each undergoing both alginate impressions and intraoral scanning using either the iTero or Trios scanner. The plaster models were measured with a caliper, while the digital models were measured virtually. In the iTero group, all tooth width measurements exhibited differences compared to the plaster values, except for maxillary left lateral incisors (p = 0.179), mandibular right (p = 0.285), and left (p = 0.073) central incisors. The Trios group did not display significant differences in any of the tooth width measurements. Intermolar width comparisons for both groups indicated differences, except for mandibular primary canine to primary canine values (p = 0.426) in the iTero group. Regarding arch length, the mandibular anterior, maxillary right, and left arch lengths in the iTero group demonstrated larger caliper values than those of iTero. Conversely, in the Trios group, all parameters showed smaller caliper values, especially in upper anterior, maxillary right, mandibular right, and mandibular left arch lengths with significance (p = 0.027, 0.007, 0.003, and 0.047, respectively). Despite the differences between the two groups, digital models might be clinically suitable alternatives for plaster models. Pediatric dentists should carefully assess these differences, as a comprehensive evaluation would result in precise orthodontic treatment planning and favorable outcomes for young patients with mixed dentition.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.304-308
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• 2000

Surface roughness measurement system with capacitance type gap sensor. Tentative result from the calibration measurement showed the potential applicability of the sensor to the processed specimen. In order to test the sensitivity of the measurement system, several parameters including valley depth, width of the specimen have been changed. Effect of the charge area between sensor and specimen surface has been also analyzed.

• Transactions of Materials Processing
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• v.10 no.5
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• pp.425-432
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• 2001

In order to investigate the influences of process parameters on the shape of lead frame, experimental study has been carried out. In the experiment, dimensional accuracy of the die sets, measurement accuracy has been managed carefully enough to simulate actual lead frame blanking process. With the blanking of square-shaped specimen, the effects of clearance, strip holding pressure and bridge width on the shape of blanked profile have been investigated. Experimental results show that the burnish ratio is increased as the clearance decreases. the strip holding pressure increases, and bridge width increases. Although the results seems to be similar to the ordinary blanking, the lead frame blanking shows a subtle different characteristics to the ordinary blanking due to the narrow bridge width.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.4 no.1
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• pp.11-20
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• 1974

The author conducted an experiment using P-A Cephalography of 242 male and female subjects of ages ranging 2-6, 7-15, and adult group. By means of Nakago's method of measurement, the standard value of Korean was obtained. The results were as follows; 1. In the group of an age, the male value was greater slightly than female value. 2. In each age group the difference between the right and left widths could be recognizable, however, it was not much great. 3. In each group, regardless of sex, the growth relation was clearly distinguishable at PO, ARI, ARE, MG, AG, and CAW. 4. When the standard value of adult Korean was compared with that of Japanese, Japanese was great with respect to the width of maxillary portion and Korean was great with respect to the width of mandibular portion. 5. Maximum head width of white man was almost similar to that of Korean, however, maxillary alveolar base width of white man was considerably small or the dental arch was narrow.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.16 no.1
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• pp.18-29
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• 1990

In this report, the variation of skin surface between before treatment and after treatment was investigated by skin image analyzer. The 30 volunteers were applied cream and lotion on the forearm Inside for 4 weeks, and the measurement parameter of skirl surface was adopted peak, length, height, and width. The results were as follows ; 1. variation trends of parameters was showed that number of peaks were increased, but length, height and width were decreased. 2. The order of improvement for skin surface are as follow ; height > length > peak > width. 3. And also disclosed that the number of peak has a correlation with width, and length has a correlation with height.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.8
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• pp.1233-1241
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• 2010

This study analyzes the body characteristics of high school boys according to 3 different body types in order to improve the fit of upper garments. First, among the lateral body types, the straight body type was selected from the SizeKorea 3D scanned data and 2D measurement data. Second, high school boys (classified as straight lateral body type) were grouped into type B, A, and Y drop groups. The percentages of type B, type A, type Y are 17.8%, 48.1%, 32.1% respectively. The characteristics of the body types were analyzed. While the bust circumference were the same among the three body types (chest width, back width, back across shoulder, and bust width did not show a significant difference); however, waist and hip measurements showed a significant difference among the three body types. Third, the height of the high school boys ranged between 165cm and 180cm and the bust circumference between 85cm and 97cm. For the bust size categories, type B and type Y are distributed similarly; however, type A is distributed in the smaller bust size categories.

• Journal of Korean Dental Science
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• v.15 no.2
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• pp.132-140
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• 2022

Purpose: Dental diagnostic records derived from study models are a popular method of obtaining reliable and vital information. Conventional plaster models are the most common method, however, they are being gradually replaced by digital impressions as technology advances. Moreover, three-dimensional dental models are becoming increasingly common in dental offices, and various methods are available for obtaining them. This study aimed to evaluate the accuracy of the measurement of dental digital models by comparing them with conventional plaster and to determine their clinical validity. Materials and Methods: The study was conducted on 16 patients' maxillary and mandibular dental models. Tooth size (TS), intercanine width (ICW), intermolar width (IMW), and Bolton analysis were taken by using a digital caliper on a plaster model obtained from each patient, while intraoral scans were manually measured using two digital analysis software. A one-way analysis of variance test was used to compare the dental measurements of the three methods. Result: No significant differences were reported between the TS, the ICW and IMW, and the Bolton analysis through the conventional and two digital groups. Conclusion: Measurements of TS, arch width, and Bolton analysis produced from digital models have shown acceptable clinical validity. No significant differences were observed between the three dental measurement techniques.

• The Journal of the Korean dental association
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• v.10 no.3
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• pp.155-158
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• 1972

As a factor of dentistry, the form of the tooth especially the size plays an important part. And in orthodontics the relation between the tooth size, arch length and the basal arch is regarded important, and it is closely related to the extraction and retension probolem in treatment planning. The auther's study of the mesio-distal crown diameters of permanent teeth, width and length of the dental arch and basal arch from the cast of 50 men and 53 women who could be measured clerly, among 102 men and 107 women regarded as the normal occlusion showed the followings. 1. Table 1 and table 2 showed the measurement of the mesio-distal maximum width of the permanent teeth, width and length of the dental arch and basal arch of the upper and lower dentitions. 2. Men's mesio-distal width of the teeth, arch length and arch width of the upper and the lower dentition, basal arch width and basal arch length are larger than those of wonen's 3. We compared the Koreans with the American white. Upper central incisors, upper first molars and lower second premolars of the latter were larger than those of the former. And the Koreans's rest tooth of the rest were comparatively larger.

• Journal of the Korean Home Economics Association
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• v.11 no.1
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• pp.14-25
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• 1973

The measurements includings 22 items such as height, weight, body width were carried out for Korean male and female students, one hundred each, from 18 to 24 years old. The correlation coefficient was calculated for every two items. The values are basic for the Clothing construction and the Pattern grading. The results are as follows : 1) The measuring values are as shown in Table 1 and the index are as shown in Table 2. 2) The correlation coefficient of length to length is larger than that of length to girth and that of length to width. The correlation coefficient of girth to girth is larger than girth to length and that of girth to width. The correlation coefficient of width to width does not show remarkable difference from those of others. 3) The correlation coefficient values of weight to lengths, weight to lengths, weight to girths and weight to width are larger. Among these, the correlation coefficient of weight to girths is the largest. 4) The correlation coefficient in general shows almost positive values except a few exception showing negative values. 5) No meaning differences are found between males and females.

• Special Issue of the Society of Naval Architects of Korea
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• 2013.12a
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• pp.73-80
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• 2013

From broad point of view, seam tracking has been one of main issues with respect to welding automation. Several attempts have been successful for seam tracking of fixed weaving width. As a solution of the seam tracking methods for varying groove width, the visual sensors such as CCD cameras have been adopted. Although the vision sensing techniques can achieve high accuracy, the weak point is that well-prepared vision sensor environment should be required to obtain high-quality visual measurements which can be easily affected by significant noises in industrial areas. This paper proposed an alternative seam tracking algorithm for narrow groove. A special measurement device for arc voltage, in this study, is developed to enhance the reliability of the measured welding signals. Based on the developed arc sensor algorithm, an automatic weld-width tracking algorithm is also proposed, which is able to predict the weld-position more accurately. The usefulness of the automatic weld-width tracking algorithm was well verified by applying it to gas tungsten arc welding (GTAW).