• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.521-526
• /
• 2004

In order to evaluate the effect of blasting vibration in buildings and it's resident located around blasting construction field in urban area, blasting vibration characteristics were measured the vibration level, vibration velocity. The 250g and 750g of charged powder were used at the apartment and at the ground, respectively. In the measurement of the ground, Z(perpendicularity) axis was the highest value in vibration level, but vertical axis was the highest value at 25m point and longitudinal axis was the highest value at 50m point in vibration velocity. The amount of measurement was high value when measuring point is higher than blasting source, while that of measurement was low value when measuring point is lower than blasting source. In the measurement of the apartment, 2 axis was the highest value in vibration level, but in vibration velocity transverse axis was the highest value at ground, was vertical axis at 1st floor, was longitudinal axis at 3rd floor and was vertical and longitudinal axis at 5th floor. The vibration level and the vibration velocity of 50m point showed higher correlation value than 25m point at the ground, but those of 25m point showed higher correlation value than 50m point at the apartment.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.14 no.7
• /
• pp.632-638
• /
• 2004

In order to evaluate the effect of blasting vibration in buildings and it's resident located around blasting construction field in urban area, blasting vibration characteristics were measured by the vibration level, vibration velocity. The 250g and 750g of charged powder were used at the apartment and at the ground, respectively. In the measurement of the ground, 2 (perpendicularity) axis was the highest value in vibration level, but vertical direction was the highest value at 25 m point and longitudinal direction was the highest value at 50 m point in vibration velocity. The amount of measurement was high value when measuring point is higher than blasting source, while that of measurement was low value when measuring point is lower than blasting source. In the measurement of the apartment, Z axis was the highest value in vibration level, but in vibration velocity transverse direction was the highest value at ground, was vertical direction at 1st floor, was longitudinal direction at 3rd floor and was vertical and longitudinal direction at 5th floor. The vibration level and the vibration velocity of 50 m point showed higher correlation value than 25 m point at the ground, but those of 25 m point showed higher correlation value than 50 m point at the apartment.

• Korean Chemical Engineering Research
• /
• v.47 no.5
• /
• pp.565-571
• /
• 2009

This study was conducted to evaluate hydrocarbon and water dew points of natural gas. For this purpose, algorithm of suppressing divergence was devised to evaluate hydrocarbon dew point up to near critical point and algorithm for finding water dew points lower than that of hydrocarbon, which cannot be calculated by commercial dew point program, was developed. The evaluated values were compared to commercial program and ISO reference values, and the results showed that deviations were zero.

• Physical Therapy Korea
• /
• v.26 no.3
• /
• pp.76-83
• /
• 2019

Background: The hyoid bone is the only non-jointed structure among the skeletal tissues of the head and neck region, and its movement and posture depend on the attached muscle, ligament, and fascia. The location of the hyoid bone is important for airway maintenance, vocalization, chewing, swallowing, breathing, and head and scapular position. In general, the location of the hyoid bone is measured using radiographs and 3D computed tomography, and no studies have reported on clinical measurement methods. Objects: This study was performed to suggest clinical measurement methods for lateral deviation of the hyoid bone and to evaluate their reliability. Methods: In this study, 24 healthy volunteers (12 males, 12 females) in Cheongju-si participated. Two examiners performed the center point test and lateral motion test twice each to measure the lateral displacement of the hyoid bone. The reliability of the center point test was analyzed using intra-class correlation coefficients (ICC), and the reliability of the lateral motion test was analyzed using Cohen's kappa coefficient. Results: The intra-rater reliability of the center point test was good, and the inter-rater reliability was moderate. The intra- and inter-rater reliability of the lateral motion test showed substantial reliability. Conclusion: Based on these results, the center point test and the lateral motion test can be used as an alternative methods of the measurement of lateral deviation of the hyoid bone for people who have musculoskeletal disorders of the head, neck, and scapula.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.49 no.5
• /
• pp.59-70
• /
• 2021

This study was to investigate the measurement point of root collar diameter of landscape trees in Korea. It may contribute to avoiding disputes caused by the difference in measurement criteria of root collar diameter of landscape trees between tree growers and constructors. The difference between landscape trees' root collar diameter measurement point was 3.59cm from 6cm underground to the surface and 1.35cm from 0cm to 6cm above ground. The source root collar diameter measurement point difference was larger in the basement than in the ground. The standard deviation of the root collar diameter of the landscape tree was 0.64 from 6cm underground to the surface, and the difference in standard deviation from 0cm to 6cm above ground was 0.16. The difference by measurement point of the root collar diameter was larger in the basement than in the ground. It has been proposed to set the reasonable measurement point of the landscaping tree root collar diameter at the inflection point where the standard deviation of the tree trunk diameter is the smallest in line with the size change of the standard for each root collar diameter measurement point. By tree species, Cornus officinalis Siebold & Zucc. 18cm above the ground, Chionanthus retusus Lindl. & Paxton. 12cm above the ground, Zelkova serrata (Thunb.) Makino. 12cm above the ground, Celtis sinensis Pers. 12cm above the ground, Styrax japonicus Siebold & Zucc. 10 cm above the ground, Cornus officinalis Siebold & Zucc. 10cm above the ground, Acer palmatum Thunb. ex Murray. 6cm above the ground, Ilex rotunda Thunb. 6cm above the ground, Quercus myrsmaefolia Blume. 4cm above the ground, Lagerstroemia indica L. 2cm above the ground The above heights were shown as reasonable measurement points. The difference by landscape tree root collar diameter measurement site showed that the standard deviation was small throughout the tree species, and the reasonable average measurement point with a stable slope of the deviation was 12cm or more on average. It can be said that the reasonable measurement point of the root collar diameter of a landscape tree is set at an average of 12cm above the ground. However, recognizing 30cm, which is a familiar ruler(尺) in traditional practices, is quick, It was recommended to measure at the height of 30cm from the surface for a reasonable measurement point of the root collar diameter of a landscape tree, for the uniformity of measurement standards.

• Korean Journal of Optics and Photonics
• /
• v.12 no.2
• /
• pp.103-108
• /
• 2001

In this paper, we designed and made the scanned point detecting system for 3-dimensional measurement of the light emitted from plasma display panel (PDP) , and we measured and analyzed 3-dimensional light emitted from a real PDP by using this scanned point detecting system. The scanned point detecting system has a point detector with a pinhole. The light emitted from the source at the in-focus position can pass through the pinhole and be collected by detector. The light from other sources at outof-focus positions is focused at points in front of or behind the pinhole, and thus it is intercepted by the pinhole. Therefore, we can detect light information from a particular point of a PDP cell of 3-dimensional structure. We know the electric field distribution inside the PDP cell from the 3-dimensionallight intensity distribution measured by using the scanned point detecting system. As the Z axial measurement increases, the intensity of light detected increases and intensity of light detected on the inside edge of the ITa electrode is larger than outside edge of the ITa eletrode and gap of the ITa electrodes. Also, as the measurement point moves from one barrier rib to another, the detected light is weaker near to the barrier ribs than at the center between the barrier ribs. The emitted light is concentrated at the center between barrier ribs. ribs.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.7 no.4
• /
• pp.600-610
• /
• 1995

When combustion gas is cooled down below the dew point of sulfuric acid vapor in the heat recovery systems, condensation occurs. Since the condensed sulfuric acid solution causes low-temperature corrosion in materials, it is important to measure the SOx dew point by electric measurement. In this study, two kinds of probes having electric gaps of 1mm or 2mm were used. and experiments were carried out by the parameters of sulfuric acid vapor and water vapor concentration. The changes of electric current caused by sulfuric acid condensed on the surface of probe according to the cooling rate and the probe head surface temperature were sudied. The opimum cooling rate was decreased with the increasing of water vaper concentration regardless of sulfuric acid concentration. The sensitivity of electric current is improved for the narrower gap(1mm) of ring electrodes, but it rarely affects the SOx dew point measuring of different probes according to the change of cooling rate.

• Journal of Science Education
• /
• v.39 no.3
• /
• pp.446-456
• /
• 2015

We have analyzed affecting factors of boiling point measurement and proposed to improve these after identifying errors of boiling point experiment in 7th grade science textbooks of 2009 revised curriculum. In the result of analyzing affecting factor of boiling point measurement for nine kinds of science textbooks, we have identified six affecting factors like as types of thermometer, heating instrument, sealing or not of stopper, position of thermometer, shape of container, and volume ratio of material and container. When performing experiment of boiling point measurement, we identified the best results when heating with a hot plate, positioning thermo sensor of MBL near neck branch after filling and sopping 10% volumes of material in round bottom flask. Based on this result, we have compared nine kinds of 7th grade science textbooks and found many errors that must be corrected in most of textbooks. Therefore it should be improved the experiment of science textbooks to enhance the understanding of students and to prevent from misconceptions for boiling point measurement.

• IE interfaces
• /
• v.11 no.1
• /
• pp.199-205
• /
• 1998

This paper describes the development of on-the-machine measuring(OMM) system which can directly measure the two and three dimensional machined accuracy using a scanning probe in milling machine. Two algorithms, NC program based continuous path(CP) measurement and CAD data assisted point to point(PTP) measurement, are developed for three dimensional measurements, with consideration of the characteristics of the scanning probe. The algorithms are used to develop an auto measuring system. The delveloped system is compared with the CMM (Coordinate Measuring Machine) in terms of accuracy and repeatability. The OMM system is expected to realize measurement time reduction and hence result in high productivity.

• Wind and Structures
• /
• v.20 no.2
• /
• pp.315-326
• /
• 2015

To overcome the drawbacks of the traditional contact-type sensor for structural displacement measurement, the vision-based technology with the aid of the digital image processing algorithm has received increasing concerns from the community of structural health monitoring (SHM). The advanced vision-based system has been widely used to measure the structural displacement of civil engineering structures due to its overwhelming merits of non-contact, long-distance, and high-resolution. However, seldom currently-available vision-based systems are capable of realizing the synchronous structural displacement measurement for multiple points on the investigated structure. In this paper, the method for vision-based multi-point structural displacement measurement is presented. A series of moving loading experiments on a scale arch bridge model are carried out to validate the accuracy and reliability of the vision-based system for multi-point structural displacement measurement. The structural displacements of five points on the bridge deck are measured by the vision-based system and compared with those obtained by the linear variable differential transformer (LVDT). The comparative study demonstrates that the vision-based system is deemed to be an effective and reliable means for multi-point structural displacement measurement.