• Journal of Computational Design and Engineering
• /
• v.1 no.4
• /
• pp.272-288
• /
• 2014

This paper presents a two-step, semi-automated method for reconstructing a three-dimensional (3D) shape of the prostate from a 3D transrectal ultrasound (TRUS) image. While the method has been developed for prostate ultrasound imaging, it can potentially be applicable to any other organ of the body and other imaging modalities. The proposed method takes as input a 3D TRUS image and generates a watertight 3D surface model of the prostate. In the first step, the system lets the user visualize and navigate through the input volumetric image by displaying cross sectional views oriented in arbitrary directions. The user then draws partial/full contours on selected cross sectional views. In the second step, the method automatically generates a watertight 3D surface of the prostate by fitting a deformable spherical template to the set of user-specified contours. Since the method allows the user to select the best cross-sectional directions and draw only clearly recognizable partial or full contours, the user can avoid time-consuming and inaccurate guesswork on where prostate contours are located. By avoiding the usage of noisy, incomprehensible portions of the TRUS image, the proposed method yields more accurate prostate shapes than conventional methods that demand complete cross-sectional contours selected manually, or automatically using an image processing tool. Our experiments confirmed that a 3D watertight surface of the prostate can be generated within five minutes even from a volumetric image with a high level of speckles and shadow noises.

• Journal of Advanced Navigation Technology
• /
• v.26 no.6
• /
• pp.464-473
• /
• 2022

In this paper, about a lightweight design that satisfies the performance of UHF-GPS Antenna used in autonomous underwater vehicle is proposed. Structural analysis, watertight external pressure test and non-destructive testing used in the design process are decided in consideration of structural safety for operating external forces in the underwater environment. First, the material of radome is selected for the performance of the UHF-GPS Antenna for communication with the carrier on the underwater operation in consideration of the 20 bar pressure generated. And the material of radome as PA-GF is selected by conducting electromagnetic field analysis and structural analysis and by considering high strength, rigidity and high dielectric constant. Electromagnetic field analysis and structural analysis by the thickness of radome are additionally performed in order to satisfy the required weight of UHF-GPS antenna. After selecting the final model, its structural safety is verified through watertight external pressure test and non-destructive testing.

• Journal of the Society of Naval Architects of Korea
• /
• v.37 no.3
• /
• pp.69-77
• /
• 2000

This study was a part of FSA study which was initiated by IMO and was applied to hatchway watertight integrity of bulk carriers. Hazards which were involved in high risk level were identified as follows. Ship Operation out of Design Criteria(Hatch Coaming Damage) and Poor Maintenance & Inspection(Securing Arrangement Damage). The potential risk was calculated by risk analysis and risk control option was made to reduce potential risk. The potential risk was about U$60,000/ship-year and could be reduced to about U$30,000/ship-year by applying RCO 1(Advanced system directly related to Hatchway Security). In addition, effectiveness of RCOs was shown by cost benefit assessment.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.14 no.1
• /
• pp.21-28
• /
• 2015

A Tsunami damper, which is installed on the outer wall of a nuclear power plant, is usually used as a ventilation window of the machine room, but can serve as a device for preventing flooding of the machine room when large waves flow over the outer wall. The sealing strip, which is inserted between the casing and the blades, plays an important role in maintaining a watertight environment. In this study, in order to ensure an effective watertight performance of the tsunami damper, FE analysis is conducted to compare the contact characteristics of sealing strips with three different section shapes. In the analysis, the casing and the blade of Tsunami damper are assumed to be rigid bodies; the sealing strip is assumed to be a flexible body. The stress, the strain, and the contact pressure are investigated to examine the sealing performance of each model.

• Journal of Korean Neurosurgical Society
• /
• v.53 no.5
• /
• pp.300-302
• /
• 2013

Reports of traumatic leptomeningeal cysts (TLMC) are rare in adults. The standard treatment approach is craniectomy with careful exposure of the intact dural edges, followed by duroplasty. However, occasionally, the location of the TLMC makes achieving watertight duroplasty impossible. Herein, we report the case of a 28-year-old male who presented with a soft growing mass on the vertex of his head 16 months after the head trauma. Upon enhanced CT examination, a bony defect involving both the inner and outer table of the cranium was observed close to the sagittal sinus, and a well-defined cystic mass, 5 cm in diameter, was nested within the defect. The risks associated with extension craniotomy were high because the lesion was located superficial to the sagittal sinus, we opted to use fibrinogen-based collagen fleece (TachoCombR$^{(R)}$) to repair the dural defect. Two months after surgery, the patient remained asymptomatic with a good cosmetic result. In cases like ours, when the defect is near the major sinuses and the risk of rupturing the sinus during watertight dural closure is high, fibrinogen-based collagen fleece (TachoCombR$^{(R)}$) is an effective alternative approach to standard dural suture techniques.

• Proceedings of KOSOMES biannual meeting
• /
• 2018.06a
• /
• pp.25-25
• /
• 2018

• Journal of Navigation and Port Research
• /
• v.29 no.10 s.106
• /
• pp.865-870
• /
• 2005

Because there are only a limited number of means of action that are available for the master to pursue in the event of flooding, onboard decision support system has been required. The majority of systems activated during a flooding emergency (such as watertight and semi-watertight doors, bulkhead valves, dewatering pumps etc.) almost exclusively aim to restore a sufficiently high level of subdivision to prevent flooding from spreading through the ship. Even though assuming the flooding scenario is not catastrophic, the use of ballast tanks can be an additional and very effective tool to ensure both prevention of flooding spreading and also improve ship stability. This paper describes an optimization algorithm devised to choose the set of ballast tanks that should be filled in order to achieve an optimal response to a flooding accident.

• Journal of Advanced Marine Engineering and Technology
• /
• v.35 no.5
• /
• pp.654-660
• /
• 2011

This paper dealt with a design guide of LED luminaires to replace the surface and watertight fluorescent lamp (FL) fixtures for naval vessels. Several standards such as Korean Industrial Standard (KS), Korea Defence Standard (KDS) and US Military Standard (MIL) were compared in terms of safety and performance of lighting fixtures. The electrical and optical characteristics like power consumption, total luminous flux, and illumination distribution of the FL fixtures were experimentally analyzed to acquire design rules for LED luminaires. Based on the results, four types of LED luminaires were fabricated, and we proposed a design guide of LED luminaires for naval vessels which save power consumption of 44~51 [%] and increase total luminous flux of 8~13 [%].

• Journal of the Korean GEO-environmental Society
• /
• v.19 no.10
• /
• pp.27-34
• /
• 2018

The effect of cutting-off the leakage was identified by the cement based wall mass constructed in underground, as complete facilities for reinforcement in shear strength of landfill which was subjected to circular failure and for cutting-off the leachate from the costal waste landfill. By (1) visual inspection after underground excavating and (2) compressive strength test for core of underground wall, it could be identified that quality of wall mass constructed in underground was so effective, and by additional test, so as (3) in-situ permeability test in the hole after coring wall mass, (4) analyzing the characteristics of basic components and their profiles through the series of chemical experiments and (5) deciding the general distribution patterns from the chromatograms using GC-MS, it could be identified that watertight and cutting-off the leachate of wall mass constructed in underground was very effective. Therefore, it is concluded that five types of tests suggested in this study can judge the effect of cutting-off the leakage or infiltration of very high concentrated leachate from the waste landfill.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.13 no.3
• /
• pp.13-24
• /
• 1993

The influence of the bubble structure and strength characteristics on the freeze-thaw resistance of high strength concrete is investigated by the laboratory experiment. The test conditions are formed in the manner that water is continueusly supplied externally and the specimens were received severe weather actions from ordinary to significantly low temperatures. The experiments are performed in two stages. In the first stage, the relation between the durability to frost action and the bubble structure is analyzed especially with respect to the water-cement ratio and the amount of air. The AE and non-AE concrete specimens made of ordinary portland cement are used in the test. In the second stage, the non-AE concrete specimens using vibratory compaction to improve the durability to frost action, and the high watertight specimens of rapid hardening portland cement to increase their initial strength are produced and tested. The degree of watertightness of the specimens is determined by measuring the permeability of the specimens and the bubble structure of the high watertight concrete is also estimated.