• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.73-84
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• 1994

Using a model system that can compare the before and after of canal preparation in the same tooth, we measured the area of the cross section, and canal wall thickness of the distal portion of the mesial root of the mandibular molar, and compared the amount of reduction in the canal using hand flared preparation the Gates-Glidden drill flared preparation according to the changes in the MAF. The results were as follows. 1. After canal preparation, the canal wall thickness had no significant difference between the hand flared preparation and Gates-Glidden drill flared preparation. 2. The canal wall thickness, after canal preparation, there was no significant difference between the sizes of the MAF. 3. The area variation range of each cross section of root had no significant difference between MAF size and methods of canal preparation. 4. After canal preparation, the frequency of the canal wall thickness under 0.5mm showed 3.5mm below the furcation to be the most frequent with statistical significance(p<0.05). 2mm below the furcation and 5mm below the furcation followed but there was no statistical significance. 5. The danger zone of the mesial root of the mandibular molar seems to be around 3.5mm.

• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• v.5 no.1
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• pp.58-63
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• 2002

This paper presents a mechanical design of the deepwater pipeline wall thickness using the recent design rules. Characteristics and limitations of the new codes were identified through a case study design in the Gulf of Mexico. In addition to the ASME, API, and DVD codes, the code of federal regulations (CFR) was also utilized in the design. It was found that conservatism still exists within the collapse prediction for water depth greater than 1500 m. Comparision of the results from DNV and API codes were presented.

• Journal of ILASS-Korea
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• v.28 no.2
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• pp.68-74
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• 2023

In this study, the thickness of the liquid sheet formed by a low speed impinging jet onto a wall was measured by the direct contact method. The spatial distribution characteristics of the sheet thickness in the radial and circumferential directions, and the effects of jet velocity and liquid viscosity were analyzed. The measurement results were compared with the theoretical predictions for two impinging jets. The wavy surface was observed for low viscosity water, but not for high viscosity glycerol solutions. The sheet thickness decreased as the circumferential angle or the distance from the impinging point increased. The sheet thickness increased as the liquid viscosity increased. Comparison with the theoretical predictions showed some differences from the measurement results.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.3
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• pp.285-292
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• 2011

The purpose of thise study was to measure the thickness of the sinus lateral wall using computed tomography (CT), and to find the most suitable vertical position for lateral window opening prior to sinus elevation. Thirty patients requiring sinus elevation had CT images taken with Philips Brilliance iCT. The thickness of the sinus lateral wall was measured according to its vertical position against the sinus inferior border, and its mean was calculated through three repeated measurements. When measured 2 mm above the sinus inferior border (SIB+2), the thickness of the sinus lateral wall was observed to be more than 2 mm. When measured 3 mm above the sinus inferior border (SIB +3), the sinus lateral wall was less than 2 mm in thickness. It is recommended that the lateral wall window be made 3 mm above the sinus inferior border when performing sinus elevation using the lateral approach.

• Restorative Dentistry and Endodontics
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• v.32 no.1
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• pp.9-18
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• 2007

The purposes of this study were to examine the variability of adhesive thickness on the different site of the cavity wall when used total-etch system without filler and simplified self-etch system with filler and to evaluate the relationship between variable adhesive thickness and microtensile bond strength to the cavity wall. A class I cavity in six human molars was prepared to expose all dentinal walls. Three teeth were bonded with a filled adhesive, $Clearfil^{TM}$ SE bond ana the other three teeth were bonded with unfilled adhesives, $Scotchbond^{TM}$ Multi Purpose. Morphology and thickness of adhesive layer were examined using fluorescence microscope. Bonding agent thickness was measured at three points along the axial cavity wall edge of cavity margin (rim). halfway down each cavity wall (h1f), internal angle of the cavity (ang). After reproducing the adhesive thickness at rim, h1f and ang, micro-tensile bond strength were evaluated. For both bonding agents, adhesive thickness of ang was significantly thicker than that of rim and h1f (P <0.05). As reproduced the adhesive thickness, microtensile bond strength was increased as adhesive thickness was increased in two bonding agents. Adhesive thickness of internal angle of the cavity was significantly thicker than that of the cavity margin and the halfway cavity wall for both bonding agents. Microtensile bond strength of the thick adhesive layer at the internal angle of the cavity was higher than that of the thin adhesive layer at 1,he cavity margin and the halfway cavity in the two bonding systems.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.17-22
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• 2002

Mechanical design of a deepwater pipeline wall thickness was performed by using the recent design rules. Characteristics and limitations of the new design rules were identified through a case study of a deepwater oil pipeline in the Gulf of Mexico. A design procedure was established for mechanical design of deepwater pipeline wall thickness. Comparison of the new API and DNV codes are presented.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.103-111
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• 2008

The purpose of this study is to find the way to determine the thickness of RC shear wall outriggers of tall buildings. For this, the analysis models of tall buildings with 60 stories are generated and analyzed. Then the changes of load transfer and deformation caused by the outriggers are investigated and the equation for the determination of the thickness of RC shear wall outriggers is proposed. Finally, the proposed equation is verified for the variously modified analysis models.

• Journal of Ocean Engineering and Technology
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• v.26 no.2
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• pp.1-7
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• 2012

DNV-OS-F101 includes the concept development, design, construction, operation,and abandonment of offshore pipeline systems. The main objective of this offshore standard (OS) is to ensure that pipeline systems are safe during the installation and operational period. The pipeline design philosophy also includes public safety and environmental protection. The mechanical wall thickness design of a pipeline shall follow the design objectives and safety philosophy. This new design code includes a very sophisticated design procedure to ensure a safe pipeline, public safety, and environmental protection. This paper presents the results of a parametric study for the wall thickness design of offshore pipelines. A design matrix was developed to cover the many design factors of pipeline integrity, public safety, and environmental protection. Sensitivity analyses of the various parameters were carried out to identify the impacts on offshore pipeline design.

• Structural Engineering and Mechanics
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• v.70 no.5
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• pp.563-570
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• 2019

To analyze the seismic reliability of concrete rectangular liquid storage structures (CRLSSs), assuming that the wall thickness and internal liquid depth of CRLSSs are random variables, calculation models of CRLSSs are established by using the Monte Carlo finite element method (FEM). The principal stresses of the over-ground and buried CRLSSs are calculated under three rare fortification intensities, and the failure probabilities of CRLSSs are obtained. The results show that the seismic reliability increases with the increase of wall thickness, whereas it decreases with the increase of liquid depth. Between the two random factors, the seismic reliability of CRLSSs is more sensitive to the change in wall thickness. Compared with the over-ground CRLSS, the buried CRLSS has better reliability.

• Archives of Craniofacial Surgery
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• v.10 no.2
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• pp.67-70
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• 2009

Purpose: Anatomical basis around orbit can be helpful in periorbital surgery, and there are many articles about measurement between periorbital reference points. In 1967, Jones and Evans measured the orbital wall thickness of Asian cadavers and this article has been cited more than 50 times. But there is no research in orbital thickness in Vivo. Author's idea was based on difference between live human and human cadaver. Material & Method: We conducted this study from 63 consecutive blow out fracture patients between January, 2000 to june, 2005 by collecting the bone fragments and measured the thickness of that fragment using vernia calipers. Anatomically, orbital floor is separated two area by inferior orbital fissure and we measured each area. Three areas were zone I (medial wall), zone II (medial to inferior orbital fissure) and zone III (lateral to inferior orbital fissure). Result: When the overall results were considered, the thickness of Zone I (medial wall of orbit) was average $0.131{\pm}0.006mm$ in male and $0.129{\pm}0.007mm$ in female and Zone II (medial side of orbital floor) was $0.251{\pm}0.005mm$ in male and $0.245{\pm}0.006mm$ in female, Zone III (lateral side of orbital floor) was $0.237{\pm}0.006mm$ in male and $0.226{\pm}0.006mm$ in female. There were no statistical difference between orbital wall thickness of male and female. Also, orbital wall thickness of adults measured $0.130{\pm}0.005mm$, $0.250{\pm}0.005mm$, $0.232{\pm}0.006mm$ in Zone I, Zone II, Zone III and $0.128{\pm}0.006mm$, $0.233{\pm}0.005mm$, $0.215{\pm}0.007mm$ in Zone I, Zone II, Zone III from childs, and there were no statistical difference between adult and child. Conclusion: This article is the first study about Korean orbital wall thickness, and can be helpful to periocular surgery.