• Journal of Dental Anesthesia and Pain Medicine
• /
• v.20 no.6
• /
• pp.387-395
• /
• 2020

Background: The anterior-middle superior alveolar (AMSA) anesthetic technique has been reported to be a less traumatic alternative to several conventional nerve blocks and local infiltration for anesthesia of the maxillary teeth, their periodontium, and the palate. However, its anatomic basis remains controversial. The present study aimed to determine if the pattern of cortical and cancellous bone density in the maxillary premolar region can provide a rationale for the success of the AMSA anesthetic technique. Method: Cone-beam computed tomography scans of 66 maxillary quadrants from 34 patients (16 men and 18 women) were evaluated using a volumetric imaging software for cortical and cancellous bone densities in three interdental regions between the canine and first molar. Bone density was measured in Hounsfield units (HU) separately for the buccal cortical, palatal cortical, buccal cancellous, and palatal cancellous bones. Mean HU values were compared using the Mann-Whitney U test and one-way ANOVA with post-hoc analysis. Results: Cancellous bone density was significantly lower (P ≤ 0.001) in the palatal half than in the buccal half across all three interdental regions. However, there was no significant difference (P = 0.106) between the buccal and palatal cortical bone densities at the site of AMSA injection. No significant difference was observed between the two genders for any of the evaluated parameters. Conclusions: The palatal half of the cancellous bone had a significantly lower density than the buccal half, which could be a reason for the effective diffusion of the anesthetic solution following a palatal injection during the AMSA anesthetic technique.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10b
• /
• pp.61-64
• /
• 1992

In this paper, a visual pattern recognition system is proposed, which can recognize both a pattern and its location. This system, referred to as the expanded neocognitron, has the following capabilities: (1) A higher performance in extraction of features, and (2) A new capability for recognizing the locations of patterns. This system adopts the learning and recognizing mechanism of the neocognitron. First, the ability to classify pattern is enhanced by improving the mechanisms of feature extraction and learning algorithm. Second, the function of detecting the location of each pattern is realized by developing an architecture which does not reduce structure, i.e., the unit density is constant all the way from the input stage to the output stage.

• Journal of the Korea Society for Simulation
• /
• v.7 no.2
• /
• pp.125-136
• /
• 1998

To upgrade railway traffic density without any change of signal block length between stations on existing railway lines, a new signalling system of train control "the pattern control technique" is suggested. It needs very little change to computerize the cab signal using transponders. A computer simulation system is developed to experiment the new control method. The new signalling system shows much increase of the railway traffic efficiency. The train head-way time by the fixed signalling system and the new pattern control system is analyzed. The pattern control technique shows 35% increasement of trair operation under same condition of railway and trains.nd trains.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1997.10a
• /
• pp.17-23
• /
• 1997

In the two-dimensional Finite Element Method for forming simulation, mesh generation and remeshing process are very significant. In this paper, using the modified splitting mesh generation algorithm, we can overcome the limitation of existing techniques and acquire mesh, which has optimal mesh density. A modified splitting algorithm for automatically generating quadrilateral mesh within a complex domain is described. Unnecessary meshing process for density representation is removed. Especially, during the mesh generation with high gradient density like as shear band representation, the modified mesh density scheme, which will generate quadrilateral mesh with the minimized error, which takes effect on FEM solver, is introduced.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.11 no.2
• /
• pp.27-37
• /
• 1991

The behavior of a negative buoyant flow flowing into a small reservoir is analysed by experiments and dimensional analysis. The nondimensional plunge point, head velocity, head travel distance and the dilution of density current are dependent on the inflow densimetric Froude number, Fre. The thickness of density current, flow pattern and density difference are different from two cases as follows; before the front of head arrive at the downstream end and after. Before the arrival, the thickness of density current is dependent on Fre and after the arrival, time and Fre. It was found that they can be expressed as power laws.

• International Journal of High-Rise Buildings
• /
• v.13 no.1
• /
• pp.57-67
• /
• 2024

With the requirement of high quality and three-dimensional urban development, the public space areas city-center rail transit stations is expanded from the plots defined by the road network density to the plots defined by the three-dimensional public space density, covering the internal and external paths of the plots, which brings about the resilient pattern of plot utilization. This paper uses the isochronous three-dimensional influence realm model around the station areas to quantitatively analyze and compare the surrounding three-dimensional path density of public space, and initially proposes flexible use patterns of differently scaled plots under the multi-scale plots linkage, to effectively promote the overall accessibility of the station realm space.

• Journal of Mechanical Science and Technology
• /
• v.18 no.8
• /
• pp.1418-1427
• /
• 2004

Combined formulation developed for the fluid-particle mixture is introduced to simulate the biocube-fluid mixture flow, which is utilized for sewage disposal. Some tricky boundary conditions are introduced in order to simulate the effect of screen wall and air bubble, which is injected from the bottom of sewage reservoir. It has been shown that a circulated flow pattern, which was observed in experiment, is reproduced from the present numerical simulation. Furthermore, the effect of biocube density on the distribution pattern of biocube is also studied. It has been shown that a biocube whose density is slightly smaller than that of surrounding fluid or neutrally buoyant one are optimal for the uniform distribution of biocube.

• Journal of Biosystems Engineering
• /
• v.21 no.3
• /
• pp.315-324
• /
• 1996

This study was one of a series of studies on application of machine vision and image processing to extract the geometrical features of plants and to analyze plant growth. Several algorithms were developed to measure morphological properties of plants and describing the growth development of in-situ lettuce(Lactuca sativa L.). Canopy, centroid, leaf density and fractal dimension of plant were measured from a top viewed binary image. It was capable of identifying plants by a thinning top viewed image. Overlapping the thinning side viewed image with a side viewed binary image of plant was very effective to auto-detect meaningful nodes associated with canopy components such as stem, branch, petiole and leaf. And, plant height, stem diameter, number and angle of branches, and internode length and so on were analyzed by using meaningful nodes extracted from overlapped side viewed images. Canopy, leaf density and fractal dimension showed high relation with fresh weight or growth pattern of in-situ lettuces. It was concluded that machine vision system and image processing techniques are very useful in extracting geometrical features and monitoring plant growth, although interactive methods, for some applications, were required.

• Journal of Mechanical Science and Technology
• /
• v.17 no.7
• /
• pp.966-977
• /
• 2003

This paper investigates how intentional mistuning of bladed disks reduces their sensitivity to unintentional random mistuning. The class of intentionally mistuned disks considered here is limited, for cost reasons, to arrangements of two types of blades (A and B, say). A two-step procedure is then described to optimize the arrangement of these blades around the disk to reduce the effects of unintentional random mistuning. First, a pure optimization effort is undertaken to obtain the pattern (s) of the A and B blades that yields small/the smallest value of the largest amplitude of response to a given excitation in the absence of unintentional random mistuning using Genetic Algorithm. Then, in the second step, a qualitative/quantitative estimate of the sensitivity for the optimized intentionally mistuned bladed disks with respect to unintentional random mistuning is performed by analyzing their amplification factor, probability density function and passband/stopband structures. Examples of application with simple bladed disk models demonstrate the significant benefits of using this class of intentionally mistuned disks.

• Journal of Advanced Marine Engineering and Technology
• /
• v.15 no.3
• /
• pp.45-56
• /
• 1991

This paper describes characteristics of the flow pattern of the flow past a rectangular cylinder experimentally investigated. The width-to-length ratio of the section varried from 2 to4. For the statistical treatment, autocorrelation coefficient, probability density function and power spectral density function are obtained by the digital processing technic through on-line system with a hot wire anemometer. As a results, it was found that strong periodic coherent eddies structure is sustained to about 20H downstream from the cylinder. And nearer the cylinder in the wake, the number of turbulent eddies of a large scale coherent structure are comparatively much more dominant than that of a small scale one. By the analysis of power spectrum, It was cleared that there exists a certain range of the width to length ratio between 2.5 and 3 of which the flow pattern changes abruptly with a sudden discontinuity in Strouhal number.