• Smart Structures and Systems
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• v.11 no.5
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• pp.453-476
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• 2013

DuraMote is a remote sensing system developed for the "NIST TIP project: next generation SCADA for prevention and mitigation of water system infrastructure disaster". It is designed for supervisory control and data acquisition (SCADA) of ruptures in water pipes. Micro-electro mechanical (MEMS) accelerometers, which record the vibration of the pipe wall, are used detect the ruptures. However, the performance of Duramote cannot be verified directly on a water distribution system because it lacks an acceptable recordable level of ambient vibration. Instead, a long-span cable-stayed bridge is an ideal test-bed to validate the accuracy, the reliability, and the robustness of DuraMote because the bridge has an acceptable level of ambient vibration. The acceleration data recorded on the bridge were used to identify the modal properties of the structure and to verify the performance of DuraMote. During the test period, the bridge was subjected to heavy rain, wind, and a typhoon but the system demonstrates its robustness and durability.

• Structural Engineering and Mechanics
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• v.15 no.3
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• pp.269-284
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• 2003

This paper reports a series of component tests on a lightweight floor system and a method to predict the natural frequency of the floor using a frame analysis program. Full-scale floor tests are also briefly described. DuraGal steel Rectangular Hollow Sections (in-line galvanised RHS) are used as joists, bearers and piers in DuraGal lightweight floor systems. A structural grade particleboard is used as decking. Connection stiffness between different components (bearer, joist, pier and floor decking) was determined. A 40% composite action was achieved between the RHS joist and the particleboard. Both 2D and 3D models were developed to study the effect of connection stiffness on predicting the natural frequency of DuraGal lightweight floor systems. It has been found that the degree of shear connection between the bearer and the joist has a significant influence on the floor natural frequency. The predicted natural frequencies are compared with measured values from full scale floor testing.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.6 no.1
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• pp.51-58
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• 1976

The study was performed to investigate the thickness of lamina dura of the human teeth in normal condition, which obtained from the intraoral roentgenograms of the 1200 cases taken by bisecting technique. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. With advancing age in both sexes, the lamina dura tends to become thinner as following. (equation omitted) 2. Generally, the alveolar crest is the thickest among the root surfaces, and apex, midroot followed, and the average thickness of the posterior teeth is thicker than that of the anterior teeth. 3. The mean value of the whole maxillary teeth is larger than the one of the whole mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.019㎜, which is not a significant differences.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.11 no.1
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• pp.67-74
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• 1981

The study was performed to investigae the thickness of lamina dura of the human teeth in periodontal disease, which obtained from the intraoral roentgenograms of the 122 cases taken by bisecting technic. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. Compared with the normal teeth, the thickness of lamina dura in periodontal disease is in creased in all of different ages, sexes and teeth. (equation omitted) 2. Generally, the alveolar crest portion is the thickest among the root surfaces, and midroot, apex followed, and the average thinckness of the posterior teeth is thicker than that of anterior teeth. The mean value of the whole maxillary teeth is almost same as that of mandibular teeth. On the whole cases, the differences of male and female is about 0.01㎜, which is not a significant differences.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.591-604
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• 1996

The present study evaluates the effects of dura mater barrier membranes In class III furcation defects on the regeneration of periodontal tissues in dogs. Experimental class III furcation defects were created surgically by removing alveolar bone horizontally down to 4mm from CEJ in mandibular premolars of adult dogs. Dura mater barrier membranes were applied bucco-lingually in the test group, and flap surgery only with no membranes in the control group. The healing was evaluated clinically and histologically after 8weeks. Clinically, the test group showed slight exposures of the membranes, while the control group showed no furcation exposure, The test specimens showed new bone formation coronal to the notch, while the control specimens had new bone formation up to the level of the notch. New cementum was observed in both groups. The test specimens showed functional arrangements of connective tissue fibers between new bone and new cenentum, while irregular arrangements were observed in the controls. No root resorption or ankylosis were observed in either groups,These results suggest that dura mater resorbable barrier membranes on class III furcation defects may be effective in regeneration of alveolar bone and peridontal ligament.

• Journal of Korean Neurosurgical Society
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• v.61 no.4
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• pp.503-508
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• 2018

Objective : Anterior odontoid screw fixation is a safe and effective method for the treatment of odontoid fractures. The surgical technique is recommended for perforation of the apical cortex of the dens by the lag screw. However, overpenetration of the apical cortex may lead to potentially serious complications such as damages of adjacent vascular and neural structures. The purpose of this study was to assess the role of three-dimensional computed tomography (CT) scan to evaluate the safe margin beyond dens tip to ventral dura for anterior odontoid screw fixation. Methods : We retrospectively analyzed the three-dimensional CT scans of the cervical spines in 55 consecutive patients at our trauma center. The patients included 38 males and 17 females aged between 22 and 73 years (mean age${\pm}$standard deviation, $45.8{\pm}14.2years$). Using sagittal images of 3-dimensional CT scan, the safe margins beyond dens tip to ventral dura as well as the appropriate screw length were measured. Results : The mean width of the apical dens tip was $9.6{\pm}1.1mm$. The mean lengths from the screw entry point to the apical dens tip and posterior end of dens tip were $39.2{\pm}2.6mm$ and $36.6{\pm}2.4mm$. The safe margin beyond apical dens tip to ventral dura was $7.7{\pm}1.7mm$. However, the safe margin beyond the posterior end of dens tip to ventral dura was decreased to $2.1{\pm}3.2mm$, which was statistically significant (p<0.01). There were no significant differences of safe margins beyond dens tip to ventral dura with patient gender and age. Conclusion : Extension by several millimeters beyond the dens tip is safe, if the trajectory of anterior odontoid screw is targeted at the apical dens tip. However, if the trajectory of the screw is targeted to the posterior end of dens tip, extension beyond dens tip may lead to damage immediately adjacent to the vental dura mater.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.377-392
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• 1991

The aim of this study was to investigate the thickness of alveolar lamina dura and alveolar bone height by the change of periodontal status. The periapical radiograms of the 853 cases were taken by paralleling technique. The conclusions from this study were as follows: 1. In the normal periodontal status, the alveolar lamina dura was the thickest at alveolar crest, followed by apex, midroot, and the average thickness of the posterior teeth was thicker than that of the anterior teeth. 2. In Russel's Periodontal Index 0 and 1, no significant differences of thickness were found to be 3 areas. In Russel's Periodontal Index 2 and 6, the thickness of alveolar lamina dura at alveolar crest was decreased, only. 3. In Russel's Periodontal Index 0 and 1, distance from the cemento-enamel junction to the alveolar crest was within 1.5㎜. In Russel's Periodontal Index 2 and 6, the distance was 3. increased over 1.5㎜.

• Journal of Korea Foundry Society
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• v.21 no.5
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• pp.290-295
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• 2001

We fabricated test samples containing various shape elements and surface roughness checking points for the jewelry cast master patterns by employing the 3D computer aided design (CAD), selective laser sintering (SLS) rapid prototype (RP) with the DuraForm powders. We varied the alignment angle from $0^{\circ}$ to $10^{\circ}$ at a given layer thickness of 0.08 and 0.1mm, respectively, in RP operation. Dimensions of the shape elements as well as values of surface roughness are characterized by an optical microscope and a contact-scanning profilometer. Surface roughness values of the top and vertical face increased as the alignment angle increased, while the other roughness values and shape elements variation were not depending on the alignment angle. The resolution of the shape realization was enhanced as the layer thickness became smaller. The minimum diameter of the hole, common in jewelry design, was 1.2 mm, and the shrinkage became 12% at the 1.6 mm-diameter hole, Our results implied that we face down the proposed design elements with $0^{\circ}$ alignment angle, and consider the shrinkage effect of each shape element in DuraForm RP jewelry modeling.

• Biomedical Science Letters
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• v.11 no.3
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• pp.375-382
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• 2005

This study aimed to investigate whether nociceptin is implicated in the, trigeminovascular responses to electrical stimulation of trigeminal ganglion in rats. An open cranial window was prepared on the right parietal bone of male Sprague-Dawley rats. Trigeminovascular system was stimulated by electrical stimulation of trigeminal ganglion (ETS; 5ms, 5Hz, 3V). Neonatal capsaicin treatment was performed with subcutaneous administration of capsaicin (50mg/kg) within the first 24 hours after birth. Changes in regional cerebral blood flow were continuously measured through the cranial window by laser-Doppler flowmetry, and the expression of nociceptin-like immunoreactivity was determined by immunohistochemistry. ETS caused increases in regional blood flow of pial arteriole in a voltage-dependent manner. ETS markedly and voltage-dependently increased the expression of nociceptin-like immunoreactivity in dura mater ipsilateral rather than contralateral to ETS. The nociceptin-like immunoreactivity was markedly reduced by pretreatments with calcitonin gene-related peptide(8-37) ($CGRP_{8-37},\;a\;CGRP_1$ receptor antagonist), L-733060 (a $NK_1$ receptor antagonist), and $[Nphe^1]$ nociceptin(1-13)$NH_2$ (a selective and competitive nociceptin receptor antagonist) as well as by neonatal capsaicin treatment. These results suggest that the electrical stimulation of trigeminal ganglion causes prominent expression of nociceptin within dura mater, in which not only neuropeptides inducing substance P and CGRP but also nociceptin are implicated in the trigeminovascular responses to electrical trigeminal ganglion stimulation.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.3
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• pp.458-469
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• 1997

This study was to compare the tensile bond strength and flexibility of four different soft liners(Coe-Soft, Soft Relining, Soft-Liner, Dura Base Soft) before & after thermocycling. Each soft liner was bonded to denture base resin block, and measured the tensile bond strength and modulus of elasticity using Universal testing machine. The mean value of tensile bond strength and modulus of elasticity for each experimental groups were statistically processed by SPSS(Statistical Package of Social Science). The obtained results were as follows : 1. Dura Base Soft had the highest tensile bond strength and Coe-Soft had the lowest tensile bond strength. 2. Coe-Soft had the lowest modulus of elasticity, and Dura Base Soft had the highest modulus of elasticity. 3. Thermocycling had no effects on the tensile bond strength and modulus of elasticity of all the soft liners. 4. The failure modes of Coe-Soft, Soft Relining, Soft Liner were mainly cohesive failure, and that of Dura Base Soft were mainly adhesive failure.