• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.1036-1043
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• 2022

This paper discusses about the development of a visual sensor that can be installed in an automatic mooring device to detect the berthing condition of a vessel. Despite controlling the ship's speed and confirming its location to prevent accidents while berthing a vessel, ship collision occurs at the pier every year, causing great economic and environmental damage. Therefore, it is important to develop a visual system that can quickly obtain the information on the speed and location of the vessel to ensure safety of the berthing vessel. In this study, a visual sensor was developed to observe a ship through an image while berthing, and to properly check the ship's status according to the surrounding environment. To obtain the adequacy of the visual sensor to be developed, the sensor characteristics were analyzed in terms of information provided from the existing sensors, that is, detection range, real-timeness, accuracy, and precision. Based on these analysis data, we developed a 3D visual module that can acquire information on objects in real time by conducting conceptual designs of LiDAR (Light Detection And Ranging) type 3D visual system, driving mechanism, and position and force controller for motion tilting system. Finally, performance evaluation of the control system and scan speed test were executed, and the effectiveness of the developed system was confirmed through experiments.

• Clinical and Experimental Pediatrics
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• v.48 no.9
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• pp.998-1003
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• 2005

Purpose : We evaluated the occurrence of renal scarring in children with unilateral vesicoureteral reflux(VUR), and the relationships between renal scar formation and risk factors such as VUR, duration of fever, acute-phase reactant, age, and sex. Methods : We retrospectively analyzed the data of 35 children newly diagnosed with unilateral vesicoureteral reflux after urinary tract infection(UTI) in Wallace Memorial Baptist Hospital between January 1996 and December 2004. Ultrasonography, Erythrocyte sedimentation rate(ESR), and C-reactive protein(CRP) were performed initially. Voiding cystourethrography(VCUG) was performed 1 to 3 weeks after treatment with UTI. $^{99m}Tc$-dimercaptosuccinic acid(DMSA) scan was performed 4 to 6 months after treatment. Results : Scintigraphic renal damage was present in 29 percent of the refluxing and in 3 percent of the nonrefluxing kidneys(P<0.05). The severity of VUR was significantly correlated with renal scar formation(P<0.05). The duration of fever before treatmen($5.0{\pm}1.3$ vs $2.6{\pm}1.3$) and prolonged fever of over 5 days were significantly different between renal scar group and non-renal scar group(P<0.05). ESR($56.3{\pm}23.8$ vs $27.9{\pm}18.1mm/hr$, P<0.05) and CRP($12.8{\pm}7.3$ vs $3.9{\pm}3.8mg/dL$, P<0.05) at the diagnosis of UTI in the renal scar group were higher, compared to those of the non-renal scar group. There were no significant differences in age and sex between the two groups. Conclusion : The presence and grade of VUR, the duration of fever before treatment, prolonged fever over 5 days, ESR, and CRP were risk factors for renal scarring, irrespective of age and sex. Diagnosis and management of VUR, in children with UTI, is important to prevent renal scars.

• Journal of the Korean Home Economics Association
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• v.49 no.3
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• pp.113-121
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• 2011

This study developed a method of calculating dynamic wearing ease (DWE) to make patterns for coverall work clothing. The DWE was measured from 3D body scan data of women in their 20's (n = 10). The body postures adopted for measuring the DWE were sitting and deep bending postures. Three types of experimental patterns (A, B, C) were developed. The DWE was applied at the waist and hip lines of the pattern. The location and size of the DWE varied from one pattern to another. For pattern B, DWE of 8.8cm was applied at the back of the waistline. For pattern C, 5.3cm was applied at the waist for the center back line, and 3.5cm was applied at the under hip level. The comfort of the experimental clothing was evaluated in six body postures. The results showed that patterns B and C were comfortable at the crotch, shoulders, and arm pits. Pattern C was comfortable at the hip and crotch areas in the arms lifting-up posture and the stepping-up posture. The appearance and fit of the experimental clothing were evaluated by the panels. Patterns B and C fitted better than pattern A at the abdomen. The results suggest that DWE should be applied at the waist and hip levels for making coverall work clothing patterns.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.6
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• pp.877-890
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• 2019

This study investigated the location of grading lines and grading amount defined by 17 women's wear brands for a pants item by target age groups (20-30, 30-40, and 40-50). This study utilized 6th Size Korea data and a script-based on a 3D scan measurement program to analyze the increase rate of body size in order to suggest a grading deviation distribution ratio for the pants using regression analysis. This study found that most brands appropriately divided grading amount at front thigh girth and back hip girth into the side and center by 1:1. Most brands divided the grading amount at the front hip girth into the side and center by 1:1; however, the ratio found from Size Korea is 0.8:1.2 for the 20-30 age group, 0.7:1.3 for the 30-40 age group, and 0.6:1.4 for the 40-50 age group. Regarding the back thigh girth, the brands targeting 20-30s, 30-40s, and 40-50s respectively assigned the grading amount into the side and center by 1:1, 1:1.2, and 1:1.3. However, the ratio found from Size Korea is 1.4:0.6 for the 20-30 age group, 1.7:0.3 for the 30-40 age group, and 1.3:0.7 for the 40-50 age group. The results can be utilized in improving the grading system of the pants item.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.177-186
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• 2021

For disaster management and mitigation of earthquakes in Korea Peninsula, active fault investigation has been conducted for the past 5 years. In particular, investigation of sediment-covered active faults integrates geomorphological analysis on airborne LiDAR data, surface geological survey, and geophysical exploration, and unearths subsurface active faults by trench survey. However, the fault traces revealed by trench surveys are only available for investigation during a limited time and restored to the previous condition. Thus, the geological data describing the fault trench sites remain as the qualitative data in terms of research articles and reports. To extend the limitations due to temporal nature of geological studies, we utilized a terrestrial LiDAR to produce 3D point clouds for the fault trench sites and restored them in a digital space. The terrestrial LiDAR scanning was conducted at two trench sites located near the Yangsan Fault and acquired amplitude and reflectance from the surveyed area as well as color information by combining photogrammetry with the LiDAR system. The scanned data were merged to form the 3D point clouds having the average geometric error of 0.003 m, which exhibited the sufficient accuracy to restore the details of the surveyed trench sites. However, we found more post-processing on the scanned data would be necessary because the amplitudes and reflectances of the point clouds varied depending on the scan positions and the colors of the trench surfaces were captured differently depending on the light exposures available at the time. Such point clouds are pretty large in size and visualized through a limited set of softwares, which limits data sharing among researchers. As an alternative, we suggested Potree, an open-source web-based platform, to visualize the point clouds of the trench sites. In this study, as a result, we identified that terrestrial LiDAR data can be practical to increase reproducibility of geological field studies and easily accessible by researchers and students in Earth Sciences.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.6
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• pp.332-336
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• 2012

Objectives: This study sought to evaluate fixation methods and determine the best method for the postoperative stabilization of maxillary osteotomy. For our analysis we performed a three-dimensional finite element analysis of stress distribution on the plate, screw, and surrounding bone, as well as displacement onto the plate. Materials and Methods: We generated a model using synthetic skull scan data; an initital surface model was changed to a solid model using software. Modified anterior segmental osteotomy (using Park's method) was made using the program, and four different types of fixation methods were used. An anterior load of 100 N was applied on the palatal surface of two central incisors. Results: The Type 1 (L-shaped) fixation method gave stresses of 187.8 MPa at the plate, 45.8 MPa at the screw, and 15.4 MPa at the bone around the plate. The Type 2 (I-shaped) fixation method gave stresses of 186.6 MPa at the plate, 75.7 MPa at the screw, and 13.8 MPa at the bone around the plate. The Type 3 (inverted L-shaped) fixation method gave stresses of 28.6 MPa at the plate, 29.9 MPa at the screw, and 15.3 MPa at the bone around the plate. The Type 4 (I-shaped) fixation method gave stresses of 34.8 MPa at the plate, 36.9 MPa at the screw, and 14.9 MPa at the bone around the plate. The deflection of the plates for the four fixation methods was 0.014 mm, 0.022 mm, 0.017 mm, and 0.018 mm, respectively. Conclusion: The Type 3 (inverted L-shaped) fixation method offers more stability than the other fixation methods. We therefore recommend this method for the postoperative stabilization of maxillary osteotomy.

• Korean Journal of Applied Biomechanics
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• v.29 no.3
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• pp.197-204
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• 2019

Objective: The purpose of this study was to identify the effect of high-heels (HH) modification on metatarsal stress in female workers. Method: Seven females who work in clothing stores ($heights=160.4{\pm}3.9cm$; $weights=47.4{\pm}4.1kg$; $age=31.3{\pm}11.1yrs$; $HH\;wear\;career=8{\pm}6.5yrs$) wore two types of HH (original and modified). The modified HH had been grooved with 1.5 cm radius and 0.2 cm depth around the first metatarsal area inside of the shoes using the modified shoe-last. Participants were asked to walk for 15 minutes on a treadmill and to stand for 10 minutes with original and modified HH, respectively. Kinetics data were collected by the F-scan in-shoe system. After each test, participants were asked to rate their perceived exertion using the Borg's 15-grade RPE scale and interviewed about their feeling of HH. Nonparametric Wilcoxon signed-rank test and effect size (Cohen's d) were used to determine the difference of the variables of interest between the original and modified HH. Results: In the present study, modified HH of the peak contact pressure of 1st metatarsal (PCP) left, PCP right, pressure time integral (PTI) left, peak pressure gradient (PPG) left during standing and PPG right during walking are greater than original HH. And even it didn't show statistically significant, the average in all pressure values of modified HH showed bigger than original HH. It surmised to be related to awkward with modified HH. Even though they said to feel the comfortable cause of big space inside of HH in the interview, they seemed to be not enough time to adapt with new HH. So their walking and standing postures were unstable. Conclusion: Modified the fore-medial part of HH can reduce the stress in the first metatarsal head and big toe area during standing and walking.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.337-349
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• 2006

Seven hundred and fifty one fractures of the rhyolitic tuffaceous rock masses were mapped using 6 scanlines placed on rock slope exposures that were within 8.02 km of Busan-Ulsan highway. These data were analyzed to find the number of fracture sets that exist in the rock slopes and the probability distributions of orientation, spacing, trace length and fracture size in 3-D for each of the fracture sets. All the fracture set orientation distributions exhibit high variability. The Fisher distributions were found to be unsuitable to represent the statistical distribution of orientation for most of the fracture sets. The probability distributions, gamma, exponential and lognormal were found to be highly suitable to represent the distribution of spacing and semi-trace length of fracture sets. In obtain-ing these distributions, corrections were applied for sampling biases associated with spacing and trace length. The generated fracture system in 3-D was used to make predictions of fracture traces for each fracture set on 2-D win-dows. Developed stochastic 3-D fracture network for the rock mass was validated by comparing statistical proper-ties of the observed fracture traces on scanlines with the predicted fracture traces on the scanlines. This exercise fumed out to be successful.

• Korean Journal of Heritage: History & Science
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• v.44 no.2
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• pp.76-95
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• 2011

After dismantled, Mireuksajiseoktap(Stone pagoda of Mireuksa Templesite) is being in the stage of restoration design. Now, different ways - producing restoration model, a 3 dimension simulation - have been requested to make more detailed and clearer restoration design prior to confirmation of its restoration design and actual restoration carry-out. This thesis proposes the way to build the detailed model for better restoration plan using extensively-used Reverse Engineering technique and Rapid Prototyping. It also introduces each stage such as a 3-dimension actual measurement, building database, a 3-dimension simulation etc., to build a desirable model. On the top of that, this thesis reveals that after dismantled, MIruksaji stone pagoda's interior and exterior were not constructed into pieces but wholeness, so that its looks can be grasped in more virtually and clearly. Secondly, this thesis makes a 3-dimension study on the 2-dimension design possible by acquiring basic materials about a 3-dimension design. Thirdly, the individual feature of each member like the change of member location can be comprehended, considering comparing analysis and joint condition of member. Lastly, in the structural perspective this thesis can be used as reference materials for structure reinforcement design by grasping destructed aspects of stone pagoda and weak points of the structure. In dismantlement-repair and restoration work of cultural properties that require delicate attention and exactness, there may be evitable errors on time and space in building reinforcement and restoration design based on a 2-dimension plan. Especially, the more complicate and bigger the subject is, the more difficult an analysis about the status quo and its delicate design are. A series of pre-review, based on the 3-dimension data according to actual measurement, can be one of the effective way to minimize the possibility that errors about time - space happen by building more delicate plan and resolving difficulties.

• Spatial Information Research
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• v.23 no.5
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• pp.41-52
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• 2015

MOLIT (Minister of Land, Infrastructure and Transport) authorized Indoor Spatial Information as Basic spatial information in 2013. It became a legal evidence for constructing and managing Indoor Spatial Information. Although it has a little advantage to utilize as service level that Indoor Spatial Information by laser scan or measurement, it has a lot of problems such as consuming many resources, requiring additional progresses for inputting Object Information. In conclusion, it is inefficient to utilize for the maintenance and domestic AEC/FM field. The purposes of this study is to output Indoor Spatial Information by operating IFC model which based on open BIM and to improve availability of Indoor Spatial Information with data visualization. The open-sources of IFC Exporter, a inner program of Revit (Autodesk Inc), is used to output Indoor Spatial Information. Directs 3D Library is also operated to visualize Indoor Spatial Information. It is possible to inter-operate between XML format and the objects of Indoor Spatial Information. It can be utilized in various field as well. For example COBie linkage in facility management, construction of geo-database using air-photogrammetry of UAV (Unmaned Areal Vehicle), the simulation of large-scale military operations and the simulation of large-scale evacuation. The method that is purposed in this study has outstanding advantages such as conformance with national spatial information policy, high level of interoperability as indoor spatial information objects based on IFC, convenience of editing information, light level of data and simplifying progress of producing information.