• Journal of the Korean Society for Precision Engineering
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• v.15 no.11
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• pp.180-188
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• 1998

Z-map is a special form of discrete nonparametric representation in which the height values at grid points on the xy-plane are stored as a 2D array z[i.j]. While z-map is the simplest form of representing sculptured surfaces and it is the most versatile scheme for modeling nonparametric objects, its practical application in industry (eg, tool-path generation) aroused much controversy over its weaknesses ; accuracy, singularity (eg, vertical wall), and some excessive storage needs. Although z-map has such limitations, much research on the application of z-map can be found in various articles. However, research on the systematic analysis of sculptured surface shape representation via z-map model is rather rare. Presented in this paper are the following: shape modeling power of the simple z-map model, exact (within tolerance) B-map representation of sculptured surfaces which have some feature-shapes such as vertical-walls and real sharp-edges by adopting some complementary B-map models, and some application examples.

• International Journal of CAD/CAM
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• v.6 no.1
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• pp.183-192
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• 2006

A CAD/CAM system has been developed for rapid prototyping (RP) of microfluidic devices based on excimer laser micromachining. The system comprises of two complementary softwares. One, the CAM tool, creates part programs from CAD models. The other, the Simulator Tool, uses a part program to generate the laser tool path and the 2D and 3D graphical representation of the machined microstructure. The CAM tool's algorithms use the 3D geometry of a microstructure, defined as an STL file exported from a CAD system, and process parameters (laser fluence, pulse repetition frequency, number of shots per area, wall angle), to automatically generate Numerical Control (NC) part programs for the machine controller. The performance of the system has been verified and demonstrated by machining a particle transportation device. The CAM tool simplifies part programming and replaces the tedious trial-and-error approach to creating programs. The simulator tool accepts manual or computer generated part programs, and displays the tool path and the machined structure. This enables error checking and editing of the program before machining, and development of programs for complex microstructures. Combined, the tools provide a user-friendly CAD/CAM system environment for rapid prototyping of microfluidic devices.

• Structural Engineering and Mechanics
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• v.58 no.5
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• pp.905-929
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• 2016

This paper assesses efficiency of the continuum method as the idealized system of building structures. A modified Coupled Two-Beam (CTB) model equipped with classical and non-classical damping has been proposed and solved analytically. In this system, complementary (non-classical) damping models composed of bending and shear mechanisms have been defined. A spatial shear damping model which is non-homogeneously distributed has been adopted in the CTB formulation and used to equivalently model passive dampers, viscous and viscoelastic devices, embedded in building systems. The application of continuum-based models for the dynamic analysis of shear wall systems has been further discussed. A reference example has been numerically analyzed to evaluate the efficiency of the presented CTB, and the optimization problems of the shear damping have been finally ascertained using local and global performance indices. The results reveal the superior performance of non-classical damping models against the classical damping. They show that the critical position of the first modal rotation in the CTB is reliable as the optimum placement of the shear damping. The results also prove the good efficiency of such a continuum model, in addition to its simplicity, for the fast estimation of dynamic responses and damping optimization issues in building systems.

• KIEAE Journal
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• v.13 no.3
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• pp.33-40
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• 2013

The world population is consuming more than 1/3 of the total energy for heating housings. Particularly in our country, 21% of the consumption energy is occupied by building section. Therefore, it is necessary to increase the energy efficiency in buildings, thus promoting a comfortable residential environment while minimizing energy consumption. Accordingly, this study presents considerations for implementing high-insulated and airtight passive houses. This study selected four houses with passive house design applied, performed building energy performance through PHPP2007, a German passive house design simulation program, and compared the building-specific heat loss and heat gain. As a result, the most vulnerable part to heat loss was turned out to be a window and the heat loss was caused by outer wall, roof, and ventilation. Accordingly, for the implementation of passive house, it is necessary to make a careful plan and airtight construction that are complementary to various parts through the energy performance analysis started from the design phase.

• Biomedical Science Letters
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• v.24 no.4
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• pp.292-304
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• 2018

Microbes is becoming increasingly forensic possibility as a consequence of advances in massive parallel sequencing (MPS) and bioinformatics. Human DNA typing is the best identifier, but it is not always possible to extract a full DNA profile namely its degradation and low copy number, and it may have limitations for identical twins. To overcome these unsatisfactory limitations, forensic potential for bacteria found in evidence could be used to differentiate individuals. Prokaryotic cells have a cell wall that better protects the bacterial nucleoid compared to the cell membrane of eukaryotic cells. Humans have an extremely diverse microbiome that may prove useful in determining human identity and may even be possible to link the microbes to the person responsible for them. Microbial composition within the human microbiome varies across individuals. Therefore, MPS of human microbiome could be used to identify biological samples from the different individuals, specifically for twins and other cases where standard DNA typing doses not provide satisfactory results due to degradation of human DNA. Microbial forensics is a new discipline combining forensic science and microbiology, which can not to replace current STR analysis methods used for human identification but to be complementary. Among the fields of microbial forensics, this paper will briefly describe information on the current status of microbiome research such as metagenomic code, salivary microbiome, pubic hair microbiome, microbes as indicators of body fluids, soils microbes as forensic indicator, and review microbial forensics as the feasibility of microbiome-based human identification.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.213-214
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• 2023

Positioning information of workers is important for safety management at construction sites. Among the various indoor positioning technologies, geomagnetic fields-based technology is more economical and has less error than other technologies. However, there is a problem that the installation and dismantling of materials such as formwork at construction sites can cause degradation in positioning performance. Therefore, in this study, the distortion of the geomagnetic field near euro-form was quantitatively measured and the application method of geomagnetic field-based indoor positioning technology on formwork stage was presented. The results showed that the distortion occurred within 10cm of the wall and column form, but positioning accuracy could be affected up to 60cm from the form due to the characteristic of geomagnetic field-collecting technology. Therefore, applying this technology to the formwork stage requires complementary measures, such as using other positioning techniques up to 60 cm near the formwork, or excluding distorted area when positioning. It is expected that this study can contribute to the efficient safety management of workers by suggesting ways to prevent an increase in positioning error when applying geomagnetic field sequence-based indoor positioning technology during the formwork stage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1552-1559
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• 2004

In order to evaluate the potential utilization value as a novel probiotic strain, the immunopotentiating activities of the cellular components from Lactobacillus brevis FSB-1 were examined. L. brevis FSB-1 isolated from kimchi were fractionated into the whole cell, cell wall, cytosol and extracellular preparation, and each fraction was examined on intestinal immune system modulating activity in vitro. The cell wall and cytosol preparation showed the relatively high bone marrow cell proliferating activity through Peyer's patch cell in a dose-dependent manner. But these preparations did not directly stimulate the bone marrow cell proliferation. The whole cell, cell wall and cytosol preparation also induced considerable levels of macrophage activation and mitogenicity of murine splenocytes in vitro. The anti-complementary activity (ITCH_(50)) of the cytosol fraction of L. brevis FSB-1 was the most potent in the cellular components, and the activity showed dose dependency. The complement activation by the cytosol fraction of L. brevis FSB-1 occurs via both alternative and classical pathways, which confirmed by the crossed immunoelectrophoresis using anti-human C3.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.1
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• pp.11-18
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• 2018

The study aims to address the energy crisis and realize self-sufficiency of building as part of local energy independence, breaking away from a single concentrated energy supply system. It is intended to develop modules of the outside insulation composite panels that conform to passive certification criteria and for site-assembly systematization. The method of study first identifies trends and passive house in literature and advanced research. Second, the target performance for development is set, and the structural material is selected and designed to simulate performance. Third, a test specimen of the passive outside insulation curtain wall module designed is manufactured and constructed to test its heat transmission coefficient, condensation performance and airtightness. Finally, analyze performance test results, and explore and propose ways to improve the estimation and improvement of incomplete causes to achieve the goal. The final test results achieved the target performance of condensation and airtightness, and the heat transmission coefficient was $0.16W/(m^2{\cdot}K)$, which is $0.01W/(m^2{\cdot})K$ below the performance target. As for the lack of performance, we saw a need for a complementary design to account for simulation errors. It also provided an opportunity to recognize that insulated walls with performance can impact performance at small break. Thus, to be commercialized into a product with the need for improvement in the design of the joint parts, a management system is needed to increase the precision in the fabrication process.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.301-308
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• 2020

Based on the analysis of fire escape situations in public facility, this study was intended to propose a design of emergency light suitable for fire in public facility. A video analysis was conducted to understand the evacuation situation of public facility because the fire could not be randomized due to the disaster. Through video analysis, we were able to identify inconvenience and necessary needs in avoiding fire in public facility and reflected them in the design of emergency light, etc. As a result of the design of emergency light, the wall type induction lamp had different LED layout structures to minimize the thickness of the product. Ceiling induction lamps have been supplemented for additional installation in corridors of complex structures. The results of this study are designed based on the criteria used in the manufacture of actual emergency light and we intend to explore ways to be practical through further experiment measurements and complementary steps through expert advice.

• Journal of Chest Surgery
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• v.30 no.12
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• pp.1205-1213
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• 1997

This study reviewed useful aspects of the intraoperative transesophageal echocardiography among the patients in whom heart surgery were undertaken between January 1996 and July 1996 at St.Pauls hospital, Medical College of Catholic University, Seoul, Korea. During that period, 61 patients were operated on because of valvular heart disease(25 patients), coronary artery disease(22 patients), congenital heart disease(13 patients), and combined coronary artery disease and valvular heart disease(1 patient). Two patients(1 redo-VSD and 1 valvular heart diease) needed repeated aortic cross clamping and complementary procedures because of incomplete initial procedures. There was no incidence of air embolism. We could observe significant relationship of cardiac output monitoring methods either by thermodilution technique and transesophageal echocardiography by linear regression analysis(p<0.001). We tested myocardial response(percentage of systolic wall thickness, PSWT) with low dose dobutamine challenge to predict post-CABG myocardial perfusion. And the test showed statistically significant resp.onse(sensitivity 76%, specificity 94.7%, positive predictive value 95%, negative predictive value 75%). These results suggest that cardiac surgeon could draw more benefits by intraoperative transesophageal echocardiography.