• Research in Mathematical Education
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• v.22 no.4
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• pp.261-282
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• 2019

The research related to testing pupils' achievement in the field of Measurement and Measure in initial teaching of geometry points to an insufficient adoption of the basic components of the length measurement concept among pupils. In order to discover the cause, we looked at the basic components on which the procedure of measuring length using a ruler is based, highlighted the possibilities of introducing the procedure in measuring length, and determined pupils' achievement during the procedure of measuring length using a ruler. The research sample consisted of 145 pupils, out of which 72 were the 2^nd grade pupils and 73 were the 4^th grade pupils. A descriptive method was applied in the research. The technique we used was testing, and for the statistical data processing we used a χ² test. The results of the research show that, when drawing a straight line of a given length using a ruler, there is no statistical difference in achievement between the 2^nd and 4^th grade pupils, nor in the pupils' knowledge regarding drawing a ruler independently, while drawing a straight line of a given length using a "broken" ruler 4^th grade pupils are statistically better. The results of the research indicate that pupils' achievement is better in doing standard tasks than in non-standard ones, given that the latter require conceptual knowledge. The components of the concept of length measurement using ruler have not been sufficiently developed yet, and these include: zero-point, partitioning a measured object in a series of consecutive measurement units and their iteration. We shed more light on the critical stage in the procedure of length measurement - the transition from non-standard to standard units and the formation of the length measurement scale. For further research, we propose to look at the formation of the concept of length measurement using the ruler through all its components and their inclusion in the mathematics curriculum, as well as examining the correlation of pupils' achievement in the procedure of measuring length with their achievement in measuring area (and volume).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.116-120
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• 1991

Technique of length measurement error is widely used in the accuracy assessment of CMMS(Coordinate measuring machines) and machine tools, as it is simple and direct measurement within the working volume of a machine. In this paper, a new method is proposed for the evaluation of the length measurement error in relation to the volumetric accuracy. lD, 2D, and 3D measuring lines are considered for recpective length measurement error: 1D, 2D, and 3D length measurement uncertainties are evaluated from volumetric accuracy. The relationship between the volumetric accuracy md length measurement error to is discussed. PC based system for length measurement error evaluation and simulation is developed.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.792-801
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• 1996

A thinning algorithm -based image analysis technique was developed to measure corn root lengths. The root length measurement method was evaluated by comparing thread lengths measured by the image analysis system with actual thread lengths. The length measurement method accurately estimated actual thread lengths (less than 2% calculated error). Also, a rapid root length density measurement procedure, which utilizes the above root length measurement method, was developed to estimate corn root length density without washing the roots. Root length densities estimated from the cut soil surface of core samples taken from the field were paired with the root length densities determined from washed roots from the same soil core sample. A linear relationship between these two values was expected and was found. Eliminating the root washing procedure reduces the time required for measuring corn root length density substantially.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.1
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• pp.39-50
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• 2013

This study estimates the measurements required to make garments but omitted from Size Korea 2010. Before the estimation of the measurements, the differences of the measurement methods were reviewed through previous research related to clothing construction and various measurement protocols that include previous Size Korea 2010 projects and ISO. The research target was 308 females aged 20 to 30 who lived in Seoul and the surrounding Gyeonggi province. A total of 43 measurements were obtained by the direct measurement method and analyzed in this study. In addition, 17 measurements which differ from the measurement method were also measured directly. These 17 measurements items were waist height, waist back height, waist height natural indentation, body rise, rise length, waist back length 1 & 2, posterior shoulder length 1 & 2, arm length 1 & 2, upper arm circumference 1 & 2, elbow circumference 1 & 2, and waist circumference 1 & 2. To analyze the differences in measurements, the subjects were divided into 2 age groups (20's and 30's). The results were as follows: First, there were big differences in stature, waist height, shoulder length, total length, and neck shoulder point to breast points by age groups; however, there were no differences in 17 measurement (such as shoulder angles) by age groups. Second, it was determined that 'waist circumference 1 & 2', 'waist back length 1 & 2', 'arm length 1 & 2', 'elbow circumference 1 & 2', 'upper arm circumference 1 & 2' and 'body rise & rise length' had significant differences by measurement methods in the entire group as well as each age group. Third, the values of 8 measurements omitted from Size Korea 2010 were estimated using similar measurements. The results of the correlation analysis were utilized to select reasonable independent measurements. Finally, 10 regression equations were obtained by regression analysis; subsequently, these will be useful for estimation of omitted measurements in Size Korea 2010.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.11
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• pp.94-100
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• 2000

This paper proposes a method of geometric error calibration for a parallel using only sensor of length measurement without additional sensors. The concept is generalized which creates measurement residuals by exploring conflicting information provided with external length sensing. Although this calibration method requires many configurations, it has an advantage of using relatively simple length measurements. This method is shown to provide good calibration results, especially when there exist smaller measurement noises and more configurations are measured.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.326-331
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• 2012

Purpose: Length measurement from maxillary anterior teeth root tip to nasal floor is incorrect in panoramic radiography. Comparison of cone beam computed tomography (CBCT) and panoramic radiography should be helpful in determining the vertical length. Methods: Sixty nine patients were taken CBCT and panoramic radiography of the maxillary anterior. First measurement is length of parallel lines from the central incisor and lateral incisor root tip to nasal floor on CBCT. Second measurement is length of perpendicular lines from the central incisor and lateral incisor root tip to nasal floor on CBCT. Third measurement is length from the central incisor and lateral incisor root tip to nasal floor on panoramic radiographys. Results: In the first measurement of the maxillary central incisors, an average of $11.36{\pm}2.49$ mm in males and $10.49{\pm}2.17$ mm in females. In the second measurement of the maxillary central incisors, $10.41{\pm}2.42$ mm in males and $9.18{\pm}2.08$ mm in females. In the third measurement of the maxillary central incisors, $10.71{\pm}2.20$ mm in males and $9.27{\pm}2.10$ mm in females. In the first measurement of the maxillary lateral incisors, an average of $13.40{\pm}2.04$ mm in males and $11.96{\pm}2.20$ mm in females. In the second measurement of the maxillary lateral incisors, $11.25{\pm}1.82$ mm in males and $10.06{\pm}1.68$ mm in females. In the third measurement of the maxillary lateral incisors, $11.47{\pm}2.01$ mm in males and $10.13{\pm}1.70$ mm in females. Conclusion: The vertical length from root tip to nasal floor was longer in male than female (P>0.05). First measurement was longer than third measurement (P<0.05). This is the actual placement of the implant site measured on the vertical length than the length of the panorama means that there are a few more free. The first measurement was longer than 114% over the third measurement.

• Research in Mathematical Education
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• v.13 no.2
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• pp.123-139
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• 2009

In this paper some attempts have been made (a) to identify all the elementary concepts of the major concept "measurement of length" and, (b) to find the sequential order of these elementary concepts. Total 714 elementary concepts have been identified and sequenced.

• Research in Mathematical Education
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• v.25 no.3
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• pp.175-188
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• 2022

Measurement has been an important part of mathematics content students must learn through their schooling. Many studies suggest students' weak measurement learning, particularly related to length measurement, on the part of lower grade students. This difficulty has been attributed to mathematics curriculum as well as instruction. Building on a view of teaching as an interactive activity, this paper explores how a first grade teacher interacted with her students in small groups in a length measurement lesson to promote conceptual understanding as well as procedural fluency. I found that even though the teacher supported students to explain and justify what they understood, the ways the teacher interacted with students were not effective to promote students' understanding. Even though this finding is based on an analysis of a single mathematics lesson, it provides an example of challenges in promoting students' understanding through interaction with students in the context of teaching length measurement.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.281-285
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• 1996

In this paper, I made visual inspection system using Vision Board and it is consist of an illuminator (a fluorescent lamp), image input device(CCD(Charge)Coupled Device) camera), image processing system(Vision Board(FARAMVB-02), image output device(videomonitor, printer), a measuring instrument(TELMN1000). Length measurement by visual inspection system is used 100mm gauge block instead of calculating distance between camera and object, it measured horizontal and vertical length factor from 400mm to 650mm by increasing 50mm. In this place, measured horizontal and vertical length factor made use of length measurement of a injection. A measuring instrument used to compare a measured length of a injection visual inspection system with it. In conclusion, length measurement of a injection compared a measuring instrument withvisual inspecion system using length factor of 100mm guage block. Maximum error of length compared two devices a measuring instrument with visual inspection system is 0.55mm. And operation program is made up Borland C++ 3.1. By changing, it is applied to various uses.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.1
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• pp.77-84
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• 2020

PURPOSE: This study compared the activities of the trunk muscles during crutch walking to determine which of the crutch length measurements is most beneficial. METHODS: Twenty young women volunteered to participate in this study. After adjusting crutch length, the participants performed a three-point walking with nondominant leg limited in weight bearing. This study used six crutch length measurements: (1) Height-40.6cm, (2) Height'.77, (3) Olecranon-to-finger length, (4) Axillary-toheel length, (5) Arm-span length-40.6cm, and (6) Arm-span length'.77. The EMG activities of the internal oblique (IO), rectus abdominis (RA), multifidus (MF), and erector spinae (ES), muscles on the weight bearing side were monitored using wireless surface EMG. RESULTS: The EMG activities of the RA and ES appeared to be significantly different among the crutch length measurements (p<.05). The post-hoc test showed that the 'Arm-span length-40.6cm' was significantly greater in the RA activity when compared to the 'Height'.77' and 'Axillary-to-heel length' measurements, and in the ES activity when compared to 'Height'.77' measurements. Furthermore, IO/RA and MF/ES ratios showed significant differences among the crutch length measurements (p<.05). In the post-hoc test, significant difference was observed between 'Olecranon-to-finger length' and 'Arm-span length-40.6cm' for the IO/RA ratio, and between 'Height'.77' and 'Olecranon-to-finger length' and between 'Height'.77' and 'Arm-span length-40.6cm' measurement for the MF/ES ratio. CONCLUSION: These findings suggest that the 'Height'.77' measurement is relatively advantageous to optimize the activities of trunk muscles during the crutch walking, and allow simple measurements of the crutch length.