• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.152-161
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• 2017

Making precise 3D maps using Mobile Mapping System (MMS) sensors are essential for the development of self-driving cars. This paper conducts research on the extraction of 3D objects around the roads using the point cloud acquired by the MMS Light Detection and Ranging (LiDAR) sensor through the following steps. First, the digital surface model (DSM) is generated using MMS LiDAR data, and then the slope map is generated from the DSM. Next, the 3D objects around the roads are identified using the slope information. Finally, 97% of the 3D objects around the roads are extracted using the morphological filtering technique. This research contributes a plan for the application of automated driving technology by extracting the 3D objects around the roads using spatial information data acquired by the MMS sensor.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.3
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• pp.208-217
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• 2018

The maxillary anterior teeth play an important role in esthetics. The esthetic of maxillary anterior teeth is closely related to tooth morphology and also harmony with gingiva. Precise diagnosis and treatment plan are essential to satisfy patient's demand, and sometimes surrounding soft tissue management is involved to achieve the goal. Gingivectomy can be considered as one method to make esthetic restoration possible. As well as esthetics, function has to be considered in maxillary anterior teeth restoration. Definitive cast of abutment and diagnostic cast waxed up labially were superimposed with model scanner, so can provide former comfortable occlusion. This case report demonstrates functional and esthetic improvements of two patients through gingivectomy and the data of superimposed image of casts.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.140-146
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• 2020

Since the current crime prevention systems have a standard mechanism that victims request for help by themselves or ask for help from a third party nearby, it is difficult to obtain appropriate help in situations where a prompt response is not possible. In this study, we proposed and developed an automatic rescue request model and system using Deep Learning and OpenCV. This study is based on the prerequisite that immediate and precise threat detection is essential to ensure the user's safety. We validated and verified that the system identified by more than 99% of the object's accuracy to ensure the user's safety, and it took only three seconds to complete all necessary algorithms. We plan to collect various types of threats and a large amount of data to reinforce the system's capabilities so that the system can recognize and deal with all dangerous situations, including various threats and unpredictable cases.

• Clinics in Shoulder and Elbow
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• v.11 no.1
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• pp.6-12
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• 2008

With the increasing use of arthroscopy and MRI for the diagnosis of shoulder problems, SLAP (superior labrum from anterior to posterior) lesions are more commonly diagnosed, and the incidence of SLAP repair surgery is increasing. Clinical diagnosis of SLAP is difficult to achieve, and many specific physical exam maneuvers have been described. However, neither these exam maneuvers nor history can provide a definitive diagnosis of a SLAP lesion. Despite this limitation, it is helpful to establish a more precise and accurate examination and to construct a preoperative plan. The purpose of this article is to review the original descriptions for specific physical exam maneuvers in SLAP, along with statistical analysis where available. This will help clinicians in deciding which tests are useful, how they should be implemented, and how to interpret the results.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.41.1-41.1
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• 2010

IGRINS (the Immersion GRating Infrared Spectrograph) is a high resolution infrared spectrograph which is being developed by a collaboration of the University of Texas, the Korea Astronomy and Space Science Institute, and Kyung Hee University. The wavelength calibration unit of IGRINS will be situated between the telescope flange and IGRINS dewar. It will include Th-Ar hallow cathode lamp, optical elements, and gas absorption cell for the case that requires precise calibration (e.g., radial velocity observation). The system will also use a tungsten halogen lamp in an integrating sphere as a blackbody source for the flat-field imaging. IGRINS will be placed initially on the McDonald 2.7m Harlan J. Smith telescope and later on 4-8m class telescopes. We present an overview of the plan for the wavelength calibration sources and of the development process for the optical and mechanical design of the IGRINS calibration system.

• Explosives and Blasting
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• v.25 no.2
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• pp.71-78
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• 2007

In many cases of underwater blasting in South Korea, the special blasting is mainly used for deepening harbor, installing gas pipes, or well blasting to build a bridge. The procedure of well blasting is almost same with shaft blasting, but the difference is that water is filled in before blasting. In case of deepening blasting under water, the first step like drilling, arranging explosives, and wire connection is done on a barge, then the next step such as charging and tamping is accomplished under water by expert divers. Therefore, underwater blasting needs precise and exact plan before blasting. In this paper, authors would like to introduce a case of underwater blasting for deepening the Busan new port with emulsion explosives and non-electric detonators in order to get some of 8,500TEU out sized container vessels entered into the port and to make safe. Considering environment and vibration, the blasting was controlled to minimized the damage to the lighthouse nearby. It will be great help to many other blasting sites where emulsion explosives and non-electric detonators are used for underwater blasting through this case.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.2
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• pp.59-67
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• 2015

When planning for streams, adequate and definite flood control should be in the primary consideration of the planner; likewise, flood control is the basic prerequisite for the recent river restoration taking place nationwide. Planning 'safe' streams and rivers that are predictable and controllable begins from accurate survey data. In this research, we will create streams in 3D terrain models and apply them through hydraulic analysis and restoration using smart geospatial information. This process allows the extraction of more accurate data regarding streams and rivers, which makes possible precise hydraulic analysis that is superior in details to the conventional methods. The study also proposes optimal vertical section interval for efficient data processing on hydraulic analysis, applicable when LiDAR data is utilized on hydraulic analysis of urban streams. The study proposes 3D design plan and various applications for spatially planning and restoring rivers and streams.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.2
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• pp.79-87
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• 2016

As 3D geospatial information is demanded, terrestrial laser scanners which can obtain 3D model of objects have been applied in various fields such as Building Information Modeling (BIM), structural analysis, and disaster management. To acquire precise data, performance evaluation of a terrestrial laser scanner must be conducted. While existing 3D surveying equipment like a total station has a standard method for performance evaluation, a terrestrial laser scanner evaluation technique for users is not established. This paper categorizes and analyzes error sources which generally occur in terrestrial laser scanning. In addition to the prior researches about categorizing error sources of terrestrial Laser scanning, this paper evaluates the error sources by the actual field tests for the smooth in-situ applications.The error factors in terrestrial laser scanning are categorized into interior error caused by mechanical errors in a terrestrial laser scanner and exterior errors affected by scanning geometry and target property. Each error sources were evaluated by simulation and actual experiments. The 3D coordinates of observed target can be distortedby the biases in distance and rotation measurement in scanning system. In particular, the exterior factors caused significant geometric errors in observed point cloud. The noise points can be generated by steep incidence angle, mixed-pixel and crosstalk. In using terrestrial laser scanner, elaborate scanning plan and proper post processing are required to obtain valid and accurate 3D spatial information.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.6
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• pp.584-588
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• 2008

Facial asymmetry is particularly associated with mandible among other facial bones and it could be either congenital or acquired. Congenital factors are related to Treacher Collin syndrome, Pierre Robin syndrome, hemifacial microsomia and other various syndromes. Acquired factors are such as damaged or diseased growing condyles, hormonal disorder, oral mal-habit, muscular force, tumor, infection and so on. Diagnosis and treatment of facial asymmetry are complicated due to differences in sizes and positions of mandibles. The aspects of facial asymmetry is various and complicated upon each individual. Depending on causes of the facial asymmetry, there also are morphological differences. For such reasons, precise anatomical analysis and diagnosis of the facial asymmetry are essential before any surgical procedure followed by the appropriate treatment plan. This case is regarding a 21-year old patient diagnosed as the facial asymmetry due to an infantile maxillofacial surgery. Employing various morphological evaluations, potential problems during the procedure are predicted beforehand. This case reports a favorable result of sagittal split ramus osteotomy performing the oblique vertical bone cutting in posterior-superior of the mandibular second molar.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.503-513
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• 2006

The purpose of this study was to determine the distribution, prevalence and relationship of the localized periodontitis of root fusion in maxillary and mandibular molars. One hundred patients who had eight maxillary and mandibular molars(third molars excluded) were consecutively selected for the study subjects. The subjects provided a total of 800 molars, i. e., 400 maxillary and 400 mandibular molars. A decision about root fusion was made on the radiographic examination. Probing depth, plaque index, gingival index and mobility were measured. The results were as follows. 1. 15.9% of the molars had a fused root. 22% of the maxillary molars and 9.8% of the mandibular molars had a fused molars. 2. In maxillary molars, the results of probing depth, plaque index, gingival index, mobility are more higher in test group than in control group, and there was a significantly difference except plaque index of maxillary first molars group(p<0.01). 3. In mandibular molars, the results of probing depth, plaque index, gingival index, mobility are more higher in test group than in control group, and there was a significantly difference(p<0.01). As a result of this study, it can be concluded that, in management of molars with a root fusion, we should detect the molars through the precise radiographic examination, early periodontal treatment and systematic treatment plan should be chosen. And postoperative continuing supportive periodontal therapy is needed.