• Journal of Cardiovascular Imaging
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• v.31 no.4
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• pp.180-187
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• 2023

BACKGROUND: Two-dimensional (2D) transesophageal echocardiography (TEE) is commonly used for assessing patients undergoing transcatheter atrial septal defect (ASD) device closure. 3D TEE, albeit providing high resolution en-face images of ASD, is used in only a fraction of cases. We aimed to perform a comparative analysis between 3D and 2D TEE assessment for ASD device planning. METHODS: This was a prospective, observational study conducted over a period of one year. Patients deemed suitable for device closure underwent 2D and 3D TEE at baseline. Defect characteristics, assessed separately in both modalities, were compared. Using regression analysis, we aimed to derive an equation for predicting device size using 3D TEE parameters. RESULTS: Thirty patients were included in the study, majority being females (83%). The mean age of the study population was 40.5 ± 12.05 years. Chest pain, dyspnea and palpitations were the common presenting complaints. All patients had suitable rims on 2D TEE. A good agreement was noted between 2D and 3D TEE for measured ASD diameters. 3D TEE showed that majority of defects were circular in shape (60%). The final device size used had high degree of correlation with 3D defect area and circumference. An equation was devised to predict device size using 3D defect area and circumference. The mean device size obtained from the equation was similar to the actual device size used in the study population (p = 0.31). CONCLUSIONS: Device sizing based on 3D TEE parameters alone is equally effective for transcatheter ASD closure as compared to 2D TEE.

• Journal of International Society for Simulation Surgery
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• v.3 no.2
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• pp.49-59
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• 2016

3D printing is also known as additive manufacturing technique in which has been used in various commercial fields such as engineering, art, education, and medicine. The applications such as fabrication of tissues and organs, implants, drug delivery, creation surgical models using 3D printer in medical field are expanding. Recently, 3D printing has been developing for produce biomimetic 3D structure using biomaterials containing living cells and that is commonly called "3D bio-printing". The 3D bio-printing technologies are usually classified four upon printing methods: Laser-assisted printing, Inkjet, extrusion, and stereolithograpy. In the bio-printing, bio-inks (combined hydrogels and living cells) are as important components as bio-printing technologies. The presence of various types of bioinks, however, in this review, we focused on the bio-inks which enables bioprinting efficacy using hydrogels with living cells.

• Journal of International Society for Simulation Surgery
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• v.1 no.2
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• pp.83-86
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• 2014

Purpose This paper was purposed to suggest the method to produce the supportive helmet (head correction) for the infants who are suffering from plagiocephaly and to evaluate the level of transformation through 3D model. Method Either of CT or X-ray restored images has been used in making the supportive helmet (Head correction) in general, but these methods of measuring have problems in cost and safety. 3D surface measurement technology was suggested to solve such matters. Results It was to design the transformed model of the head within 0.7cm in average by scanning the surface of head and performing 3D restoration with marching cube and the changing rate of the head was compared in numerical data with 3D model. Conclusion The suggested methods displayed the better performance than the conventional method in respect of the speed and cost.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.5
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• pp.129-138
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• 2006

Composite deck plate using a pre-assembled re-bar truss for slab with corrugated zinc galvanized sheet iron at manufactory, is given the improvement on design, manufacture, and performance for construction work of cast-in-place reinforced concrete slab by enabling to cast concrete directly without the form work. There are two methods in analyzing composite deck : Simplified 2D analysis and 3D analysis. Although simplified 2D analysis is being used up to date, the use of 3D analysis, allowing for the vierendeel behavior of composite deck by real configuration correlating to bar reducing, is demanded. To compare the simplified 2D analysis applied to allowable stress design with 3D analysis applied to limit state design, 8 specimen are manufactured. Main variables include the depth of slab, the length of span, the diameter of bottom bar and lattice bar, and the presence of corrugated zinc galvanized sheet iron. The comparison from the experimental result and analytical result indicates that applying of simplified 2D analysis is possible for the use of D10 with bottom bar. However, it is more reasonable to apply 3D analysis which allows to indicate vierendeel behavior considered the real configuration.

• Journal of Sensor Science and Technology
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• v.25 no.2
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• pp.86-90
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• 2016

A 3D ultrasonic anemometer measures the direction and velocity of wind in a 3D space. The 2D ultrasonic anemometers developed by different manufacturers do not differ significantly in terms of their form or structure. The 3D ultrasonic anemometers, on the other hand, have more diverse forms than their 2D counterparts depending on the measurement algorithms and methods. Designing and reviewing the structure at the initial stage and defining its performance objectives are time-consuming processes. The process can be made cost-effective and time-saving if the validity is tested by model design and structural interpretation, and the structure is designed to withstand high wind velocities. This study presents the results of a 3D ultrasonic anemometer on real sample data by using a 3D modeling program, CATIA, for ultrasonic anemometer modeling.

• Journal of information and communication convergence engineering
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• v.19 no.2
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• pp.102-107
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• 2021

In this paper, we propose a new three-dimensional (3D) photon-counting integral imaging reconstruction method using a merging reconstruction process and maximum likelihood estimation (MLE). The conventional 3D photon-counting reconstruction method extracts photons from elemental images using a Poisson random process and estimates the scene using statistical methods such as MLE. However, it can reduce the photon levels because of an average overlapping calculation. Thus, it may not visualize 3D objects in severely low light environments. In addition, it may not generate high-quality reconstructed 3D images when the number of elemental images is insufficient. To solve these problems, we propose a new 3D photon-counting merging reconstruction method using MLE. It can visualize 3D objects without photon-level loss through a proposed overlapping calculation during the reconstruction process. We confirmed the image quality of our proposed method by performing optical experiments.

• Journal of the Ergonomics Society of Korea
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• v.33 no.4
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• pp.299-311
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• 2014

Objective: The aim of this study was to develop a method for measuring breast size from three-dimensional (3D) body scan image data. Background: Previous bra studies established reference points by directly contacting the subject's naked skin to determine the boundary of the breast. But some subjects were uncomfortable with these types of measurements. This study examined noncontact methods of extracting breast reference points from 3D body scan data that were collected while subjects were wearing standardized soft bras. Method: 3D body scan data of 32 Korean women were analyzed. The subjects were selected from the Size Korea 2010 study. The breast landmarks were identified by graphic analyses of slicing contour lines on 3D body scan data. Results: Three methods determining bra cup size were compared. The M1 and M2 methods determined cup size by calculating the difference between bust girth and under-bust girth. The M3 method determined bra cup size by measuring breast arc length. Conclusion: The researchers proposed an anthropometric bra cup sizing system with the breast arc length (M3 method). It was measured from the geometrically defined landmarks on the 3D body scan slicing contour lines. The new bra cup size was highly correlated with breast depth. Application: The noncontact measuring method used in this study can be applied to the ergonomic studies measuring sensitive body parts.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.2
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• pp.55-62
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• 2000

In order to make the reasonable irrigation plan in the unripended tidal reclaimed paddy fields, the estimation of irrigation water requirements by soil textures and water management methods for the normal growth of crops is very important . This study was carried out to determine leaching requirements before cultivating crops. For the purpose of this study, the physical and chemical properties of soil samples used in the desalinization experiments were analyzed, and change of salinity by supplying water and leaching water were investigated in the experimental field with lysimeters. As a result considering the soil textures, desalinization effects of good drainage soils(S1) were better than those of poor drainage soils (S2). In the changes of salinity of the soils with supplying water by water management methods, among the good grainage soils with culvert treatment(S1CW), salinity of S1CW3 with 1, 120mm and S1W4 with 1, 440mm supplying water were 2.6dS/m and 1.1dS/m respectively, and salinity of S1NW4 with 1.680mm among those non-culvert treatment (S1NW) was 3.0dS/m, less than critical salanity value 3.0dS/m. On the other hand, of the poor drainage soils with cultvert treatment , salinity of S2CW3 was ranged 9.4-6.0dS/m with supplied water, and that of non-culverted treatment S2NW as 12.3-8.4dS/m.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.1
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• pp.59-67
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• 1995

Blood lead assay by $D_2$ lamp background correction method of atomic absorption spectrophotometer(AAS) with wavelength of 283.3 nm is most popular in occupational health practice in Korea. On the other hand, $D_2$ lamp background correction method with wavelength of 217.0 nm is also often used in general chemical analysis for lead assay in general purpose. But both methods have some weakness of background correction which brought direct effect on the results of analysis. Recently blood lead assay with polarized Zeeman effect of AAS was introduced and is now preferred in many laboratory than $D_2$ correction method in blood lead analysis. But still AAS with $D_2$ lamp are widely used in the field of occupational health in Korea. This study compared blood lead assay data with $D_2$ correction methods(283.3 and 217.0 nm) and with that of polarized Zeeman effect correction method to evaluate the validity of 02 correction methods. The results obtained were as follows; 1. Taking the value of polarized Zeeman effect method as reference value of 1.00, the mean relative value of $D_2$ correction method with wavelength of 217.0 nm was 0.92 and that with wavelength of 283.3 nm was 0.90 respectively in the analysis of blood lead whose value were below $20.0{\mu}g/dl$(p<0.001). Both mean values were statistically smaller than polarized Zeeman effect correction method. But in the analysis of blood whose value were between 20.0 to $20.0{\mu}g/dl$, the mean relative value of $D_2$ correction method was 0.96 in both wavelength and did not differ from polarized Zeeman effect method(p<0.001). There was no difference of blood lead between $D_2$ correction method and polarized Zeeman effect method in the analysis of blood lead whose value were over $40.0{\mu}g/dl$. 2. The variations of background correction value in polarized Zeeman effect method were not changed by increase of blood lead, but those in $D_2$ correction methods were increased by the increase of blood lead. While then relative standard deviation(RSD) of data measured by Zeeman effect method were decreased by the increase of blood lead, those by $D_2$ methods were nol differed by the increase of blood lead.

• Radiation Oncology Journal
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• v.34 no.2
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• pp.145-155
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• 2016

Purpose: Radiation therapy targeting axilla and groin lymph nodes improves regional disease control in locally advanced and high-risk skin cancers. However, trials generally used conventional two-dimensional radiotherapy (2D-RT), contributing towards relatively high rates of side effects from treatment. The goal of this study is to determine if three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), or volumetric-modulated arc therapy (VMAT) may improve radiation delivery to the target while avoiding organs at risk in the clinical context of skin cancer regional nodal irradiation. Materials and Methods: Twenty patients with locally advanced/high-risk skin cancers underwent computed tomography simulation. The relevant axilla or groin planning target volumes and organs at risk were delineated using standard definitions. Paired t-tests were used to compare the mean values of several dose-volumetric parameters for each of the 4 techniques. Results: In the axilla, the largest improvement for 3D-CRT compared to 2D-RT was for homogeneity index (13.9 vs. 54.3), at the expense of higher lung $V_{20}$ (28.0% vs. 12.6%). In the groin, the largest improvements for 3D-CRT compared to 2D-RT were for anorectum $D_{max}$ (13.6 vs. 38.9 Gy), bowel $D_{200cc}$ (7.3 vs. 23.1 Gy), femur $D_{50}$ (34.6 vs. 57.2 Gy), and genitalia $D_{max}$ (37.6 vs. 51.1 Gy). IMRT had further improvements compared to 3D-CRT for humerus $D_{mean}$ (16.9 vs. 22.4 Gy), brachial plexus $D_5$ (57.4 vs. 61.3 Gy), bladder $D_5$ (26.8 vs. 36.5 Gy), and femur $D_{50}$ (18.7 vs. 34.6 Gy). Fewer differences were observed between IMRT and VMAT. Conclusion: Compared to 2D-RT and 3D-CRT, IMRT and VMAT had dosimetric advantages in the treatment of nodal regions of skin cancer patients.