• Restorative Dentistry and Endodontics
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• 제39권2호
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• pp.126-131
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• 2014

Among dental traumas, horizontal root fractures are relatively uncommon injuries. Proper initial management and periodical evaluation is essential for the successful treatment of a root-fractured tooth. If pulpal necrosis develops, endodontic treatment is indicated, exclusively for the coronal fragment. Fragment diastases exert a great influence on healing at the fracture line and on pulpal necrosis. An adequately treated root-fractured tooth has a good prognosis. This case report describes the treatment and 2-yr follow up of 3 maxillary central incisors, first with horizontal root fracture, second with horizontal root fracture and avulsion, and third with horizontal root fracture and lateral luxation. All three cases were treated with mineral trioxide aggregate (ProRoot, Dentsply). During 2 yr of follow-up evaluation, the root-fractured teeth of the present patients were well retained in the arch, showing periodontal healing, even after endodontic treatment.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.632-635
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• 2009

Nowadays renewable energy has undergone major development, however most renewable energy resources still have demerit which is under the influence of environmental factors that can not be set up the power plants or can not be generated the rated power. To wander from the point of environmental instability, the present paper looks at the tidal current energy which can supply regular electric power. It has an important merit which is more predictable than others, however the place which can be set up is limited and the turbine system must be optimized. The development of the optimized rotor blades design is urgent to obtain regular electric power using the tidal current energy. Therefore, the paper expands on this idea and presents a conceptual design of 100kW horizontal axis rotor blade for the tidal current turbine using blade element momentum (BEM) analysis. The compatibility of horizontal axis tidal turbine (HATT) is verified using a commercial computational fluid dynamics (CFD) code, ANSYS-CFX. This paper presents results of the numerical analysis, such as pressure, streak line and the performance curves with torque data for the inflow of the horizontal axis tidal current turbine (HATT).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.92-96
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• 2001

Although the problem of seawater intrusion at the coastal aquifer was recognized before over one hundred years at the coastal aquifer, much groundwater keep on being salinitized by several reasons such as groundwater exhaustion, coastalline change, and human activities. The horizontal and vertical electrical soundings and geostatistical methods were used to define the local characteristics of saltwater intrusion and to estimate the saltwater interface in the southeastern area of the Pusan City. The 24 points of the Schlumberger vertical electrical soundings(VES) to loom depth and the 2 lines of dipole-dipole horizontal soundings are peformed. The resistivity data have lognormal distributions. The horizontal extents of saline water intrusion were estimated from the inversion of horizontal prospecting data. Lognormal ordinary kriging is used in A-A' resistivity profiles on May and July because the data have stationary models in semivariograms. Lognormal IRF-k kriging is used for the isopleth maps using vertical resistivity data. The 10 ohm-m resistivity line on the isopleth maps of 21m, 30m, 50m, and 70m depth using resisitivity data measured in July is sifted to the east, cpomparing that of the isopleth maps measured in May. The kriged vertical and horizontal resistivity isopleth maps suggested that the geostatistical methods can be used to define the variation of earth resistivity distribution at the saltwater interface.

• 한국해양공학회지
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• 제27권1호
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• pp.59-66
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• 2013

A suction anchor is one of the most popular anchors for deepsea floating systems. An anchor used for catenary mooring is predominantly under a horizontal load. In this study, the behavior of a suction anchor installed in cohesionless soil was investigated when the anchor was mainly subjected to a horizontal load induced by a catenary line. In order to study the behavior of the suction anchor, 3D FEM analysis models were developed and analyzed. Depending on the location of the load (padeye), the ultimate horizontal load was monitored. The distributions of the reaction forces around the anchor induced by the seabed were analyzed using the circumferential stress to understand the behavior of the suction anchor under a horizontal load.

• 한국지열·수열에너지학회논문집
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• 제12권4호
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• pp.1-7
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• 2016

This paper presents a design method for the horizontal straight ground heat exchanger (GHE) based on the Kavanaugh design method. In order to examine suitability of the suggested design method, a horizontal line type GHE was installed in a steel box of which the size was $5m{\times}1m{\times}1m$ filled with dried Joomunjin standard, and a thermal response test (TRT) was conducted for 21 hours. A numerical analysis was performed for a simulation of a peak month operation and for its verification by finite element method (FEM). According to the simulation results, it was concluded that the suggested design method for a horizontal straight GHE is reliable for the estimation of a design length.

• 한국산학기술학회논문지
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• 제7권5호
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• pp.852-857
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• 2006

본 논문은 디지털 지도를 이용하여 산악지형의 전계강도를 정밀하게 분석하는 방법을 제시한다. 일반적으로 전파의 전계 강도는 직접파와 수평면 반사를 주로 고려하였으나, 산악지역에서는 직접파와 수평면 반사 외에도 산악지형의 수직면에 의한 반사도 고려해야 한다. 이러한 점을 고려하여 산악지형에서 전파를 송신할 때 일어나는 직접파와 수평면 반사파, 산악 지형에 의한 수직면 반사파의 합성 전계를 전파의 편파 특성과 위상 특성을 고려하여 계산한 결과를 제시하였다.

• 대한치과보철학회지
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• 제8권1호
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• pp.73-76
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• 1968

The author analyzed 51 Korean male adults and 53 female adults with normal occlusion roentgenocephalometrically and following conclusions were obtained. 1. The angle between the Camper line and the maxillary occlusal line was $-6.22^{\circ}$ in male and $-4.76^{\circ}$ in female. There was not a considerable difference between male and female. 2. The angle formed by the Camper line and the Frankfort Horizontal line was $18.01^{\circ}$ in male and $17.3^{\circ}$ in female. Not a significant difference was found in both sexes. 3. The angles of NSL-$OL_s$, NSL-FH and $OL_s$-FH showed no considerable differences in both sexes.

• 천문학회지
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• 제31권2호
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• pp.77-87
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• 1998

The accumulated knowledge of the influence of solar granulation on spectral lines, i.e. their asymmetry, provides a key to analyze stellar spectral line asymmetries. In this paper, a simple line synthesis using a simple 'model' of granulation was calculated. By adjusting the properties of the granule model, the observed imprints of convection on spectral lines can be reproduced. Since we depict convective flows using a continuous function rather than using a few components of flows (cf. Gray and Toner 1985, 1986; dravins 1990), we were able to identify which components of convection are important in line bisector shapes. The results of this study can be summarized as follows: Firstly, the intensity contrast (i.e. temperature fluctuation), and the area coverage of up- and down-flows are the two important factors which determine the line bisector shapes. Secondly, on the contrary to the assumption of other studies, the effect of horizontal flows is non-negligible. This exercise provides a qualitative understanding of the effect of convection on spectral lines. This knowledge serves as a guideline for understanding the characteristic difference in convection for stars on either side of the 'Granulation Boundary' (Gray 1982; Gray and Nagel 1989).

• 한국농공학회지
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• 제22권2호
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• pp.64-82
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• 1980

The aim of this thesis, when water permeates dam, is to study the shape of seepage line and seepage quantity. As for the process, various sand model dams of same capacity were constructed in the water tank : they are a central, middle, inclined, up and down stream point of which is paralled, and filter-installed types. And the slope of seepage line and seepage quantity in these various models for experiment were measured, observed data were analyzed, and several formulas which already published were compared and examined. As for the shape of seepage line, the relation between upstream water level and exit: slope of seepage line, near the entrance and exit point, geometrically similar model, and the shape of seepage line filter-installed were examined. As regards to the seepage quantity, several formulas which already published and testing result values were compared and examined, and relation with the slope of seepage line, the seepage quantity, the slope of upstream point, and the upstream water level were mutually studied. Particulary, when horizontal filter was installed, propriety of the existing formulas for effective filter length w as examined, and the relative position of exit point in various. conditions was also studied.

• 건축역사연구
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• 제22권6호
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• pp.7-22
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• 2013

The purpose of this paper is to study on the spatial characteristics from the "The Holy Trinity" fresco painted by Masaccio in the early Renaissance paintings. The results of this study are as follows. 1. The elevation composition of the "The Holy Trinity" fresco is divided into the upper and lower structure through horizontal axis on horizontal line around vanishing point. The upper structure is composed of vertical axis formed through the disposition of the "Trinity" elements and horizontal axis on horizontal line. The lower structure is composed of the sarcophagus and skeleton in such inside and the altar supported through circular columns of left and right. 2. The section composition of the "The Holy Trinity" fresco is composed of the ceiling structure of cylindrical-shaped vault on upper part around basic square floor plan that is interior space and upper structure. The exterior space and lower structure is placed with sarcophagus in inner part that altar and step is projected as same height and width in the outside direction. 3. The basic floor composition of the "The Holy Trinity" fresco is planned by square shape around structural columns that is placed at corners as symmetry through transverse, longitudinal and diagonal axis. The whole floor composition planned through the altar and step that is in exterior space at front, the apse of round form at rear part and the structure of the middle story concept at interior. 4. The visual aspect of the "The Holy Trinity" fresco is composed of the stable balance in relation with distance and height because the interior and exterior space as well as the upper structure and lower structure is formed by regular proportion system. The elevation angle of visual range was planned to view in detail generally or partially the architectural composition system and element, characters through proper visual distance, center and position.